conditional comments - Page 236

Generating moderately interesting images

- by Williham Totland

Abstract: Can you propose a mathematical-ish algorithm over a plane of pixels that will generate a moderately interesting image, preferably one that on the whole resembles something? The story thus far: Once upon a time I decided in an effort to reduce cycle waste on my (admittedly too) numerous computers, and set out to generate images in a moderately interesting fashion; using a PRNG and some clever math to create images that would, on the whole, resemble something. Or at least, that was the plan. As it turns out, clever math requires being a clever mathematician; this I am not. At some length I arrived at a method that preferred straight lines (as these are generally the components of which our world is made), perhaps too strongly. The result is mildly interesting; resembling, perhaps, city grids as such: Now for the question proper: Given the source code of this little program; can you improve upon it and propose a method that gives somewhat more interesting results? (e.g. not city grids, but perhaps faces, animals, geography, what have you) This is also meant as a sort of challenge; I suppose and as such I've set down some completely arbitrary and equally optional rules: The comments in the code says it all really. Suggestions and "solutions" should edit the algorithm itself, not the surrounding framework, except as for to fix errors that prevents the sample from compiling. The code should compile cleanly with a standard issue C compiler. (If the example provided doesn't, oops! Tell me, and I'll fix. :) The method should, though again, this is optional, not need to elicit help from your friendly neighborhood math library. Solutions should probably be deliverable by simply yanking out whatever is between the snip lines (the ones that say you should not edit above and below, respectively), with a statement to the effect of what you need to add to the preamble in particular. The code requires a C compiler and libpng to build; I'm not entirely confident that the MinGW compiler provides the necessities, but I would be surprised if it didn't. For Debian you'll want the libpng-dev package, and for Mac OS X you'll want the XCode tools.. The source code can be downloaded here. Warning: Massive code splurge incoming! // compile with gcc -o imggen -lpng imggen.c // optionally with -DITERATIONS=x, where x is an appropriate integer // If you're on a Mac or using MinGW, you may have to fiddle with the linker flags to find the library and includes. #include <stdio.h> #include <stdlib.h> #include <png.h> #ifdef ITERATIONS #define REPEAT #endif // ITERATIONS // YOU MAY CHANGE THE FOLLOWING DEFINES #define WIDTH 320 #define HEIGHT 240 // YOU MAY REPLACE THE FOLLOWING DEFINES AS APPROPRIATE #define INK 16384 void writePNG (png_bytepp imageBuffer, png_uint_32 width, png_uint_32 height, int iteration) { char *fname; asprintf(&fname, "out.%d.png", iteration); FILE *fp = fopen(fname, "wb"); if (!fp) return; png_structp png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL); png_infop info_ptr = png_create_info_struct(png_ptr); png_init_io(png_ptr, fp); png_set_filter(png_ptr, PNG_FILTER_TYPE_DEFAULT, PNG_FILTER_NONE); png_set_compression_level(png_ptr, Z_BEST_COMPRESSION); png_set_IHDR(png_ptr, info_ptr, width, height, 8, PNG_COLOR_TYPE_GRAY, PNG_INTERLACE_NONE, PNG_COMPRESSION_TYPE_DEFAULT, PNG_FILTER_TYPE_DEFAULT); png_set_rows(png_ptr, info_ptr, imageBuffer); png_set_invert_mono(png_ptr); /// YOU MAY COMMENT OUT THIS LINE png_write_png(png_ptr, info_ptr, PNG_TRANSFORM_IDENTITY, NULL); png_destroy_write_struct(&png_ptr, &info_ptr); fclose(fp); free(fname); } int main (int argc, const char * argv[]) { png_uint_32 height = HEIGHT, width = WIDTH; int iteration = 1; #ifdef REPEAT for (iteration = 1; iteration <= ITERATIONS; iteration++) { #endif // REPEAT png_bytepp imageBuffer = malloc(sizeof(png_bytep) * height); for (png_uint_32 i = 0; i < height; i++) { imageBuffer[i] = malloc(sizeof(png_byte) * width); for (png_uint_32 j = 0; j < width; j++) { imageBuffer[i][j] = 0; } } /// CUT ACROSS THE DASHED LINES /// ------------------------------------------- /// NO EDITING ABOVE THIS LINE; EXCEPT AS NOTED int ink = INK; int x = rand() % width, y = rand() % height; int xdir = (rand() % 2)?1:-1; int ydir = (rand() % 2)?1:-1; while (ink) { imageBuffer[y][x] = 255; --ink; xdir += (rand() % 2)?(1):(-1); ydir += (rand() % 2)?(1):(-1); if (ydir > 0) { ++y; } else if (ydir < 0) { --y; } if (xdir > 0) { ++x; } else if (xdir < 0) { --x; } if (x == -1 || y == -1 || x == width || y == height || x == y && x == 0) { x = rand() % width; y = rand() % height; xdir = (rand() % 2)?1:-1; ydir = (rand() % 2)?1:-1; } } /// NO EDITING BELOW THIS LINE /// ------------------------------------------- writePNG(imageBuffer, width, height, iteration); for (png_uint_32 i = 0; i < height; i++) { free(imageBuffer[i]); } free(imageBuffer); #ifdef REPEAT } #endif // REPEAT return 0; } Note: While this question doesn't strictly speaking seem "answerable" as such; I still believe that it can give rise to some manner of "right" answer. Maybe. Happy hunting.

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Project Euler #15

- by Aistina

Hey everyone, Last night I was trying to solve challenge #15 from Project Euler: Starting in the top left corner of a 2×2 grid, there are 6 routes (without backtracking) to the bottom right corner. How many routes are there through a 20×20 grid? I figured this shouldn't be so hard, so I wrote a basic recursive function: const int gridSize = 20; // call with progress(0, 0) static int progress(int x, int y) { int i = 0; if (x < gridSize) i += progress(x + 1, y); if (y < gridSize) i += progress(x, y + 1); if (x == gridSize && y == gridSize) return 1; return i; } I verified that it worked for a smaller grids such as 2×2 or 3×3, and then set it to run for a 20×20 grid. Imagine my surprise when, 5 hours later, the program was still happily crunching the numbers, and only about 80% done (based on examining its current position/route in the grid). Clearly I'm going about this the wrong way. How would you solve this problem? I'm thinking it should be solved using an equation rather than a method like mine, but that's unfortunately not a strong side of mine. Update: I now have a working version. Basically it caches results obtained before when a n×m block still remains to be traversed. Here is the code along with some comments: // the size of our grid static int gridSize = 20; // the amount of paths available for a "NxM" block, e.g. "2x2" => 4 static Dictionary<string, long> pathsByBlock = new Dictionary<string, long>(); // calculate the surface of the block to the finish line static long calcsurface(long x, long y) { return (gridSize - x) * (gridSize - y); } // call using progress (0, 0) static long progress(long x, long y) { // first calculate the surface of the block remaining long surface = calcsurface(x, y); long i = 0; // zero surface means only 1 path remains // (we either go only right, or only down) if (surface == 0) return 1; // create a textual representation of the remaining // block, for use in the dictionary string block = (gridSize - x) + "x" + (gridSize - y); // if a same block has not been processed before if (!pathsByBlock.ContainsKey(block)) { // calculate it in the right direction if (x < gridSize) i += progress(x + 1, y); // and in the down direction if (y < gridSize) i += progress(x, y + 1); // and cache the result! pathsByBlock[block] = i; } // self-explanatory :) return pathsByBlock[block]; } Calling it 20 times, for grids with size 1×1 through 20×20 produces the following output: There are 2 paths in a 1 sized grid 0,0110006 seconds There are 6 paths in a 2 sized grid 0,0030002 seconds There are 20 paths in a 3 sized grid 0 seconds There are 70 paths in a 4 sized grid 0 seconds There are 252 paths in a 5 sized grid 0 seconds There are 924 paths in a 6 sized grid 0 seconds There are 3432 paths in a 7 sized grid 0 seconds There are 12870 paths in a 8 sized grid 0,001 seconds There are 48620 paths in a 9 sized grid 0,0010001 seconds There are 184756 paths in a 10 sized grid 0,001 seconds There are 705432 paths in a 11 sized grid 0 seconds There are 2704156 paths in a 12 sized grid 0 seconds There are 10400600 paths in a 13 sized grid 0,001 seconds There are 40116600 paths in a 14 sized grid 0 seconds There are 155117520 paths in a 15 sized grid 0 seconds There are 601080390 paths in a 16 sized grid 0,0010001 seconds There are 2333606220 paths in a 17 sized grid 0,001 seconds There are 9075135300 paths in a 18 sized grid 0,001 seconds There are 35345263800 paths in a 19 sized grid 0,001 seconds There are 137846528820 paths in a 20 sized grid 0,0010001 seconds 0,0390022 seconds in total I'm accepting danben's answer, because his helped me find this solution the most. But upvotes also to Tim Goodman and Agos :) Bonus update: After reading Eric Lippert's answer, I took another look and rewrote it somewhat. The basic idea is still the same but the caching part has been taken out and put in a separate function, like in Eric's example. The result is some much more elegant looking code. // the size of our grid const int gridSize = 20; // magic. static Func<A1, A2, R> Memoize<A1, A2, R>(this Func<A1, A2, R> f) { // Return a function which is f with caching. var dictionary = new Dictionary<string, R>(); return (A1 a1, A2 a2) => { R r; string key = a1 + "x" + a2; if (!dictionary.TryGetValue(key, out r)) { // not in cache yet r = f(a1, a2); dictionary.Add(key, r); } return r; }; } // calculate the surface of the block to the finish line static long calcsurface(long x, long y) { return (gridSize - x) * (gridSize - y); } // call using progress (0, 0) static Func<long, long, long> progress = ((Func<long, long, long>)((long x, long y) => { // first calculate the surface of the block remaining long surface = calcsurface(x, y); long i = 0; // zero surface means only 1 path remains // (we either go only right, or only down) if (surface == 0) return 1; // calculate it in the right direction if (x < gridSize) i += progress(x + 1, y); // and in the down direction if (y < gridSize) i += progress(x, y + 1); // self-explanatory :) return i; })).Memoize(); By the way, I couldn't think of a better way to use the two arguments as a key for the dictionary. I googled around a bit, and it seems this is a common solution. Oh well.

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Beginning Java (Working with Arrays; Class Assignment)

- by Jason

I am to the point where I feel as if I correctly wrote the code for this homework assignment. We were given a skeleton and 2 classes that we had to import (FileIOHelper and Student). /* * Created: *** put the date here *** * * Author: *** put your name here *** * * The program will read information about students and their * scores from a file, and output the name of each student with * all his/her scores and the total score, plus the average score * of the class, and the name and total score of the students with * the highest and lowest total score. */ // import java.util.Scanner; import java.io.*; // C:\Users\Adam\info.txt public class Lab6 { public static void main(String[] args) throws IOException { // Fill in the body according to the following comments Scanner key boardFile = new Scanner(System.in); // Input file name String filename = getFileName(keyboardFile); //Open the file // Input number of students int numStudents = FileIOHelper.getNumberOfStudents(filename); Student students[] = new Student[numStudents]; // Input all student records and create Student array and // integer array for total scores int totalScore[] = new int[students.length]; for (int i = 0; i < students.length; i++){ for(int j = 1; j < 4; j++){ totalScore[i] = totalScore[i] + students[i].getScore(j); } } // Compute total scores and find students with lowest and // highest total score int maxScore = 0; int minScore = 0; for(int i = 0; i < students.length; i++){ if(totalScore[i] >= totalScore[maxScore]){ maxScore = i; } else if(totalScore[i] <= totalScore[minScore]){ minScore = i; } } // Compute average total score int allScores = 0; int average = 0; for (int i = 0; i < totalScore.length; i++){ allScores = allScores + totalScore[i]; } average = allScores / totalScore.length; // Output results outputResults(students, totalScore, maxScore, minScore, average); } // Given a Scanner in, this method prompts the user to enter // a file name, inputs it, and returns it. private static String getFileName(Scanner in) { // Fill in the body System.out.print("Enter the name of a file: "); String filename = in.next(); return filename; // Do not declare the Scanner variable in this method. // You must use the value this method receives in the // argument (in). } // Given the number of students records n to input, this // method creates an array of Student of the appropriate size, // reads n student records using the FileIOHelper, and stores // them in the array, and finally returns the Student array. private static Student[] getStudents(int n) { Student[] myStudents = new Student[n]; for(int i = 0; i <= n; i++){ myStudents[i] = FileIOHelper.getNextStudent(); } return myStudents; } // Given an array of Student records, an array with the total scores, // the indices in the arrays of the students with the highest and // lowest total scores, and the average total score for the class, // this method outputs a table of all the students appropriately // formatted, plus the total number of students, the average score // of the class, and the name and total score of the students with // the highest and lowest total score. private static void outputResults( Student[] students, int[] totalScores, int maxIndex, int minIndex, int average ) { // Fill in the body System.out.println("\nName \t\tScore1 \tScore2 \tScore3 \tTotal"); System.out.println("--------------------------------------------------------"); for(int i = 0; i < students.length; i++){ outputStudent(students[i], totalScores[i], average); System.out.println(); } System.out.println("--------------------------------------------------------"); outputNumberOfStudents(students.length); outputAverage(average); outputMaxStudent(students[maxIndex], totalScores[maxIndex]); outputMinStudent(students[minIndex], totalScores[minIndex]); System.out.println("--------------------------------------------------------"); } // Given a Student record, the total score for the student, // and the average total score for all the students, this method // outputs one line in the result table appropriately formatted. private static void outputStudent(Student s, int total, int avg) { System.out.print(s.getName() + "\t"); for(int i = 1; i < 4; i++){ System.out.print(s.getScore(i) + "\t"); } System.out.print(total + "\t"); if(total < avg){ System.out.print("-"); }else if(total > avg){ System.out.print("+"); }else{ System.out.print("="); } } // Given the number of students, this method outputs a message // stating what the total number of students in the class is. private static void outputNumberOfStudents(int n) { System.out.println("The total number of students in this class is: \t" + n); } // Given the average total score of all students, this method // outputs a message stating what the average total score of // the class is. private static void outputAverage(int average) { System.out.println("The average total score of the class is: \t" + average); } // Given the Student with highest total score and the student's // total score, this method outputs a message stating the name // of the student and the highest score. private static void outputMaxStudent( Student student, int score ) { System.out.println(student.getName() + " got the maximum total score of: \t" + score); } // Given the Student with lowest total score and the student's // total score, this method outputs a message stating the name // of the student and the lowest score. private static void outputMinStudent( Student student, int score ) { System.out.println(student.getName() + " got the minimum total score of: \t" + score); } } But now I get an error at the line totalScore[i] = totalScore[i] + students[i].getScore(j); Exception in thread "main" java.lang.NullPointerException at Lab6.main(Lab6.java:42)

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Moving items from one tableView to another tableView with extra's

- by Totumus Maximus

Let's say I have 2 UITableViews next to eachother on an ipad in landscape-mode. Now I want to move multiple items from one tableView to the other. They are allowed to be inserted on the bottom of the other tableView. Both have multiSelection activated. Now the movement itself is no problem with normal cells. But in my program each cell has an object which contains the consolidationState of the cell. There are 4 states a cell can have: Basic, Holding, Parent, Child. Basic = an ordinary cell. Holding = a cell which contains multiple childs but which wont be shown in this state. Parent = a cell which contains multiple childs and are shown directly below this cell. Child = a cell created by the Parent cell. The object in each cell also has some array which contains its children. The object also holds a quantityValue, which is displayed on the cell itself. Now the movement gets tricky. Holding and Parent cells can't move at all. Basic cells can move freely. Child cells can move freely but based on how many Child cells are left in the Parent. The parent will change or be deleted all together. If a Parent cell has more then 1 Child cell left it will stay a Parent cell. Else the Parent has no or 1 Child cell left and is useless. It will then be deleted. The items that are moved will always be of the same state. They will all be Basic cells. This is how I programmed the movement: *First I determine which of the tableViews is the sender and which is the receiver. *Second I ask all indexPathsForSelectedRows and sort them from highest row to lowest. *Then I build the data to be transferred. This I do by looping through the selectedRows and ask their object from the sender's listOfItems. *When I saved all the data I need I delete all the items from the sender TableView. This is why I sorted the selectedRows so I can start at the highest indexPath.row and delete without screwing up the other indexPaths. *When I loop through the selectedRows I check whether I found a cell with state Basic or Child. *If its a Basic cell I do nothing and just delete the cell. (this works fine with all Basic Cells) *If its a Child cell I go and check it's Parent cell immidiately. Since all Child cells are directly below the Parent cell and no other the the Parent's Childs are below that Parent I can safely get the path of the selected Childcell and move upwards and find it's Parent cell. When this Parent cell is found (this will always happen, no exceptions) it has to change accordingly. *The Parent cell will either be deleted or the object inside will have its quantity and children reduced. *After the Parent cell has changed accordingly the Child cell is deleted similarly like the Basic cells *After the deletion of the cells the receiver tableView will build new indexPaths so the movedObjects will have a place to go. *I then insert the objects into the listOfItems of the receiver TableView. The code works in the following ways: Only Basic cells are moved. Basic cells and just 1 child for each parent is moved. A single Basic/Child cell is moved. The code doesn't work when: I select more then 1 or all childs of some parent cell. The problem happens somewhere into updating the parent cells. I'm staring blindly at the code now so maybe a fresh look will help fix things. Any help will be appreciated. Here is the method that should do the movement: -(void)moveSelectedItems { UITableView *senderTableView = //retrieves the table with the data here. UITableView *receiverTableView = //retrieves the table which gets the data here. NSArray *selectedRows = senderTableView.indexPathsForSelectedRows; //sort selected rows from lowest indexPath.row to highest selectedRows = [selectedRows sortedArrayUsingSelector:@selector(compare:)]; //build up target rows (all objects to be moved) NSMutableArray *targetRows = [[NSMutableArray alloc] init]; for (int i = 0; i<selectedRows.count; i++) { NSIndexPath *path = [selectedRows objectAtIndex:i]; [targetRows addObject:[senderTableView.listOfItems objectAtIndex:path.row]]; } //delete rows at active for (int i = selectedRows.count-1; i >= 0; i--) { NSIndexPath *path = [selectedRows objectAtIndex:i]; //check what item you are deleting. act upon the status. Parent- and HoldingCells cant be selected so only check for basic and childs MyCellObject *item = [senderTableView.listOfItems objectAtIndex:path.row]; if (item.consolidatedState == ConsolidationTypeChild) { for (int j = path.row; j >= 0; j--) { MyCellObject *consolidatedItem = [senderTableView.listOfItems objectAtIndex:j]; if (consolidatedItem.consolidatedState == ConsolidationTypeParent) { //copy the consolidated item but with 1 less quantity MyCellObject *newItem = [consolidatedItem copyWithOneLessQuantity]; //creates a copy of the object with 1 less quantity. if (newItem.quantity > 1) { newItem.consolidatedState = ConsolidationTypeParent; [senderTableView.listOfItems replaceObjectAtIndex:j withObject:newItem]; } else if (newItem.quantity == 1) { newItem.consolidatedState = ConsolidationTypeBasic; [senderTableView.listOfItems removeObjectAtIndex:j]; MyCellObject *child = [senderTableView.listOfItems objectAtIndex:j+1]; child.consolidatedState = ConsolidationTypeBasic; [senderTableView.listOfItems replaceObjectAtIndex:j+1 withObject:child]; } else { [senderTableView.listOfItems removeObject:consolidatedItem]; } [senderTableView reloadData]; } } } [senderTableView.listOfItems removeObjectAtIndex:path.row]; } [senderTableView deleteRowsAtIndexPaths:selectedRows withRowAnimation:UITableViewRowAnimationTop]; //make new indexpaths for row animation NSMutableArray *newRows = [[NSMutableArray alloc] init]; for (int i = 0; i < targetRows.count; i++) { NSIndexPath *newPath = [NSIndexPath indexPathForRow:i+receiverTableView.listOfItems.count inSection:0]; [newRows addObject:newPath]; DLog(@"%i", i); //scroll to newest items [receiverTableView setContentOffset:CGPointMake(0, fmaxf(receiverTableView.contentSize.height - recieverTableView.frame.size.height, 0.0)) animated:YES]; } //add rows at target for (int i = 0; i < targetRows.count; i++) { MyCellObject *insertedItem = [targetRows objectAtIndex:i]; //all moved items will be brought into the standard (basic) consolidationType insertedItem.consolidatedState = ConsolidationTypeBasic; [receiverTableView.ListOfItems insertObject:insertedItem atIndex:receiverTableView.ListOfItems.count]; } [receiverTableView insertRowsAtIndexPaths:newRows withRowAnimation:UITableViewRowAnimationNone]; } If anyone has some fresh ideas of why the movement is bugging out let me know. If you feel like you need some extra information I'll be happy to add it. Again the problem is in the movement of ChildCells and updating the ParentCells properly. I could use some fresh looks and outsider ideas on this. Thanks in advance. *updated based on comments

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SVG as CSS background for website navigation-bar

- by Irfan Mir

I drew a small (horizontal / in width) svg to be the background of my website's navigation. My website's navigation takes place a 100% of the browser's viewport and I want the svg image to fill that 100% space. So, using css I set the background of the navigation (.nav) to nav.svg but then I saw (whenI opened the html file in a browser) that the svg was not the full-width of the nav, but at the small width I drew it at. How can I get the SVG to stretch and fill the entire width of the navigation (100% of the page) ? Here is the code for the html file where the navigation is in: <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd"> <html lang="en"><head><meta http-equiv="Content-Type" content="text/html; charset=utf-8"> <title>Distributed Horizontal Menu</title> <meta name="generator" content="PSPad editor, www.pspad.com"> <style type="text/css"> *{ margin:0; padding:0; } .nav { margin:0; padding:0; min-width:42em; width:100%; height:47px; overflow:hidden; background:transparent url(nav.svg) no-repeat; text-align:justify; font:bold 88%/1.1 verdana; } .nav li { display:inline; list-style:none; } .nav li.last { margin-right:100%; } .nav li a { display:inline-block; padding:13px 4px 0; height:31px; color:#fff; vertical-align:middle; text-decoration:none; } .nav li a:hover { color:#ff6; background:#36c; } @media screen and (max-width:322px){ /* styling causing first break will go here*/ /* but in the meantime, a test */ body{ background:#ff0000; } } </style></head><body> <ul class="nav">  <li>  <a href="#">internet explorer 6-8</a></li> <li>  <a href="#">opera 10</a></li> <li>  <a href="#">firefox 3</a></li> <li>  <a href="#">safari 4</a></li> <li class="last">  <a href="#">chrome 2</a>    </li> </ul> </body></html> and Here is the code for the svg: <?xml version="1.0" encoding="utf-8"?> <!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd"> <svg version="1.1" id="Layer_1" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" x="0px" y="0px" width="321.026px" height="44.398px" viewBox="39.487 196.864 321.026 44.398" enable-background="new 39.487 196.864 321.026 44.398" xml:space="preserve"> <linearGradient id="SVGID_1_" gradientUnits="userSpaceOnUse" x1="280" y1="316.8115" x2="280" y2="275.375" gradientTransform="matrix(1 0 0 1 -80 -77)"> <stop offset="0" style="stop-color:#5A4A6A"/> <stop offset="0.3532" style="stop-color:#605170"/> <stop offset="0.8531" 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id="seperators"> <line fill="none" stroke="#000000" stroke-width="1.0259" stroke-miterlimit="10" x1="104.5" y1="197.375" x2="104.5" y2="240.75"/> <line opacity="0.1" fill="none" stroke="#FFFFFF" stroke-width="1.0259" stroke-miterlimit="10" enable-background="new " x1="103.5" y1="197.375" x2="103.5" y2="240.75"/> <line opacity="0.1" fill="none" stroke="#FFFFFF" stroke-width="1.0259" stroke-miterlimit="10" enable-background="new " x1="105.5" y1="197.375" x2="105.5" y2="240.75"/> <line fill="none" stroke="#000000" stroke-width="1.0259" stroke-miterlimit="10" x1="167.5" y1="197.375" x2="167.5" y2="240.75"/> <line opacity="0.1" fill="none" stroke="#FFFFFF" stroke-width="1.0259" stroke-miterlimit="10" enable-background="new " x1="166.5" y1="197.375" x2="166.5" y2="240.75"/> <line opacity="0.1" fill="none" stroke="#FFFFFF" stroke-width="1.0259" stroke-miterlimit="10" enable-background="new " x1="168.5" y1="197.375" x2="168.5" y2="240.75"/> <line fill="none" stroke="#000000" 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d="M360,238.721c0,1.121-0.812,2.029-1.812,2.029 H41.813c-1.001,0-1.813-0.908-1.813-2.029v-39.316c0-1.119,0.812-2.027,1.813-2.027h316.375c1.002,0,1.812,0.908,1.812,2.027 V238.721z"/> </svg> I appreciate and welcome any and all comments, help, and suggestions. Thanks in Advance!

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program not working as expected!

- by wilson88

Can anyone just help spot why my program is not returning the expected output.related to my previous question.Am passing a vector by refrence, I want to see whats in the container before I copy them to another loaction.if u remove comments on loadRage, u will see bids are generated by the trader. #include <iostream> #include <vector> #include <string> #include <algorithm> #include <cstdlib> #include <iomanip> using namespace std; const int NUMSELLER = 1; const int NUMBUYER = 1; const int NUMBIDS = 20; const int MINQUANTITY = 1; const int MAXQUANTITY = 30; const int MINPRICE =100; const int MAXPRICE = 150; int s=0; int trdId; // Bid, simple container for values struct Bid { int bidId, trdId, qty, price; char type; // for sort and find. bool operator<(const Bid &other) const { return price < other.price; } bool operator==(int bidId) const { return this->bidId == bidId; } }; // alias to the list, make type consistent typedef vector<Bid> BidList; // this class generates bids! class Trader { private: int nextBidId; public: Trader(); Bid getNextBid(); Bid getNextBid(char type); // generate a number of bids void loadRange(BidList &, int size); void loadRange(BidList &, char type, int size); void setVector(); }; Trader::Trader() : nextBidId(1) {} #define RAND_RANGE(min, max) ((rand() % (max-min+1)) + min) Bid Trader::getNextBid() { char type = RAND_RANGE('A','B'); return getNextBid(type); } Bid Trader::getNextBid(char type) { for(int i = 0; i < NUMSELLER+NUMBUYER; i++) { // int trdId = RAND_RANGE(1,9); if (s<10){trdId=0;type='A';} else {trdId=1;type='B';} s++; int qty = RAND_RANGE(MINQUANTITY, MAXQUANTITY); int price = RAND_RANGE(MINPRICE, MAXPRICE); Bid bid = {nextBidId++, trdId, qty, price, type}; return bid; } } //void Trader::loadRange(BidList &list, int size) { // for (int i=0; i<size; i++) { list.push_back(getNextBid()); } //} // //void Trader::loadRange(BidList &list, char type, int size) { // for (int i=0; i<size; i++) { list.push_back(getNextBid(type)); } //} //---------------------------AUCTIONEER------------------------------------------- class Auctioneer { vector<Auctioneer> List; Trader trader; vector<Bid> list; public: Auctioneer(){}; void accept_bids(const BidList& bid); }; typedef vector<Auctioneer*> bidlist; void Auctioneer::accept_bids(const BidList& bid){ BidList list; //copy (BidList.begin(),BidList.end(),list); } //all the happy display commands void show(const Bid &bid) { cout << "\tBid\t(" << setw(3) << bid.bidId << "\t " << setw(3) << bid.trdId << "\t " << setw(3) << bid.type <<"\t " << setw(3) << bid.qty <<"\t " << setw(3) << bid.price <<")\t\n " ; } void show(const BidList &list) { cout << "\t\tBidID | TradID | Type | Qty | Price \n\n"; for(BidList::const_iterator itr=list.begin(); itr != list.end(); ++itr) { //cout <<"\t\t"; show(*itr); cout << endl; } cout << endl; } //search now checks for failure void show(const char *msg, const BidList &list) { cout << msg << endl; show(list); } void searchTest(BidList &list, int bidId) { cout << "Searching for Bid " << bidId << endl; BidList::const_iterator itr = find(list.begin(), list.end(), bidId); if (itr==list.end()) { cout << "Bid not found."; } else { cout << "Bid has been found. Its : "; show(*itr); } cout << endl; } //comparator function for price: returns true when x belongs before y bool compareBidList(Bid one, Bid two) { if (one.type == 'A' && two.type == 'B') return (one.price < two.price); return false; } void sort(BidList &bidlist) { sort(bidlist.begin(), bidlist.end(), compareBidList); } int main(int argc, char **argv) { Trader trader; BidList bidlist; Auctioneer auctioneer; //bidlist list; auctioneer.accept_bids(bidlist); //trader.loadRange(bidlist, NUMBIDS); show("Bids before sort:", bidlist); sort(bidlist); show("Bids after sort:", bidlist); system("pause"); return 0; }

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Solving embarassingly parallel problems using Python multiprocessing

- by gotgenes

How does one use multiprocessing to tackle embarrassingly parallel problems? Embarassingly parallel problems typically consist of three basic parts: Read input data (from a file, database, tcp connection, etc.). Run calculations on the input data, where each calculation is independent of any other calculation. Write results of calculations (to a file, database, tcp connection, etc.). We can parallelize the program in two dimensions: Part 2 can run on multiple cores, since each calculation is independent; order of processing doesn't matter. Each part can run independently. Part 1 can place data on an input queue, part 2 can pull data off the input queue and put results onto an output queue, and part 3 can pull results off the output queue and write them out. This seems a most basic pattern in concurrent programming, but I am still lost in trying to solve it, so let's write a canonical example to illustrate how this is done using multiprocessing. Here is the example problem: Given a CSV file with rows of integers as input, compute their sums. Separate the problem into three parts, which can all run in parallel: Process the input file into raw data (lists/iterables of integers) Calculate the sums of the data, in parallel Output the sums Below is traditional, single-process bound Python program which solves these three tasks: #!/usr/bin/env python # -*- coding: UTF-8 -*- # basicsums.py """A program that reads integer values from a CSV file and writes out their sums to another CSV file. """ import csv import optparse import sys def make_cli_parser(): """Make the command line interface parser.""" usage = "\n\n".join(["python %prog INPUT_CSV OUTPUT_CSV", __doc__, """ ARGUMENTS: INPUT_CSV: an input CSV file with rows of numbers OUTPUT_CSV: an output file that will contain the sums\ """]) cli_parser = optparse.OptionParser(usage) return cli_parser def parse_input_csv(csvfile): """Parses the input CSV and yields tuples with the index of the row as the first element, and the integers of the row as the second element. The index is zero-index based. :Parameters: - `csvfile`: a `csv.reader` instance """ for i, row in enumerate(csvfile): row = [int(entry) for entry in row] yield i, row def sum_rows(rows): """Yields a tuple with the index of each input list of integers as the first element, and the sum of the list of integers as the second element. The index is zero-index based. :Parameters: - `rows`: an iterable of tuples, with the index of the original row as the first element, and a list of integers as the second element """ for i, row in rows: yield i, sum(row) def write_results(csvfile, results): """Writes a series of results to an outfile, where the first column is the index of the original row of data, and the second column is the result of the calculation. The index is zero-index based. :Parameters: - `csvfile`: a `csv.writer` instance to which to write results - `results`: an iterable of tuples, with the index (zero-based) of the original row as the first element, and the calculated result from that row as the second element """ for result_row in results: csvfile.writerow(result_row) def main(argv): cli_parser = make_cli_parser() opts, args = cli_parser.parse_args(argv) if len(args) != 2: cli_parser.error("Please provide an input file and output file.") infile = open(args[0]) in_csvfile = csv.reader(infile) outfile = open(args[1], 'w') out_csvfile = csv.writer(outfile) # gets an iterable of rows that's not yet evaluated input_rows = parse_input_csv(in_csvfile) # sends the rows iterable to sum_rows() for results iterable, but # still not evaluated result_rows = sum_rows(input_rows) # finally evaluation takes place as a chain in write_results() write_results(out_csvfile, result_rows) infile.close() outfile.close() if __name__ == '__main__': main(sys.argv[1:]) Let's take this program and rewrite it to use multiprocessing to parallelize the three parts outlined above. Below is a skeleton of this new, parallelized program, that needs to be fleshed out to address the parts in the comments: #!/usr/bin/env python # -*- coding: UTF-8 -*- # multiproc_sums.py """A program that reads integer values from a CSV file and writes out their sums to another CSV file, using multiple processes if desired. """ import csv import multiprocessing import optparse import sys NUM_PROCS = multiprocessing.cpu_count() def make_cli_parser(): """Make the command line interface parser.""" usage = "\n\n".join(["python %prog INPUT_CSV OUTPUT_CSV", __doc__, """ ARGUMENTS: INPUT_CSV: an input CSV file with rows of numbers OUTPUT_CSV: an output file that will contain the sums\ """]) cli_parser = optparse.OptionParser(usage) cli_parser.add_option('-n', '--numprocs', type='int', default=NUM_PROCS, help="Number of processes to launch [DEFAULT: %default]") return cli_parser def main(argv): cli_parser = make_cli_parser() opts, args = cli_parser.parse_args(argv) if len(args) != 2: cli_parser.error("Please provide an input file and output file.") infile = open(args[0]) in_csvfile = csv.reader(infile) outfile = open(args[1], 'w') out_csvfile = csv.writer(outfile) # Parse the input file and add the parsed data to a queue for # processing, possibly chunking to decrease communication between # processes. # Process the parsed data as soon as any (chunks) appear on the # queue, using as many processes as allotted by the user # (opts.numprocs); place results on a queue for output. # # Terminate processes when the parser stops putting data in the # input queue. # Write the results to disk as soon as they appear on the output # queue. # Ensure all child processes have terminated. # Clean up files. infile.close() outfile.close() if __name__ == '__main__': main(sys.argv[1:]) These pieces of code, as well as another piece of code that can generate example CSV files for testing purposes, can be found on github. I would appreciate any insight here as to how you concurrency gurus would approach this problem. Here are some questions I had when thinking about this problem. Bonus points for addressing any/all: Should I have child processes for reading in the data and placing it into the queue, or can the main process do this without blocking until all input is read? Likewise, should I have a child process for writing the results out from the processed queue, or can the main process do this without having to wait for all the results? Should I use a processes pool for the sum operations? If yes, what method do I call on the pool to get it to start processing the results coming into the input queue, without blocking the input and output processes, too? apply_async()? map_async()? imap()? imap_unordered()? Suppose we didn't need to siphon off the input and output queues as data entered them, but could wait until all input was parsed and all results were calculated (e.g., because we know all the input and output will fit in system memory). Should we change the algorithm in any way (e.g., not run any processes concurrently with I/O)?

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Scala parser combinator runs out of memory

- by user3217013

I wrote the following parser in Scala using the parser combinators: import scala.util.parsing.combinator._ import scala.collection.Map import scala.io.StdIn object Keywords { val Define = "define" val True = "true" val False = "false" val If = "if" val Then = "then" val Else = "else" val Return = "return" val Pass = "pass" val Conj = ";" val OpenParen = "(" val CloseParen = ")" val OpenBrack = "{" val CloseBrack = "}" val Comma = "," val Plus = "+" val Minus = "-" val Times = "*" val Divide = "/" val Pow = "**" val And = "&&" val Or = "||" val Xor = "^^" val Not = "!" val Equals = "==" val NotEquals = "!=" val Assignment = "=" } //--------------------------------------------------------------------------------- sealed abstract class Op case object Plus extends Op case object Minus extends Op case object Times extends Op case object Divide extends Op case object Pow extends Op case object And extends Op case object Or extends Op case object Xor extends Op case object Not extends Op case object Equals extends Op case object NotEquals extends Op case object Assignment extends Op //--------------------------------------------------------------------------------- sealed abstract class Term case object TrueTerm extends Term case object FalseTerm extends Term case class FloatTerm(value : Float) extends Term case class StringTerm(value : String) extends Term case class Identifier(name : String) extends Term //--------------------------------------------------------------------------------- sealed abstract class Expression case class TermExp(term : Term) extends Expression case class UnaryOp(op : Op, exp : Expression) extends Expression case class BinaryOp(op : Op, left : Expression, right : Expression) extends Expression case class FuncApp(funcName : Term, args : List[Expression]) extends Expression //--------------------------------------------------------------------------------- sealed abstract class Statement case class ExpressionStatement(exp : Expression) extends Statement case class Pass() extends Statement case class Return(value : Expression) extends Statement case class AssignmentVar(variable : Term, exp : Expression) extends Statement case class IfThenElse(testBody : Expression, thenBody : Statement, elseBody : Statement) extends Statement case class Conjunction(left : Statement, right : Statement) extends Statement case class AssignmentFunc(functionName : Term, args : List[Term], body : Statement) extends Statement //--------------------------------------------------------------------------------- class myParser extends JavaTokenParsers { val keywordMap : Map[String, Op] = Map( Keywords.Plus -> Plus, Keywords.Minus -> Minus, Keywords.Times -> Times, Keywords.Divide -> Divide, Keywords.Pow -> Pow, Keywords.And -> And, Keywords.Or -> Or, Keywords.Xor -> Xor, Keywords.Not -> Not, Keywords.Equals -> Equals, Keywords.NotEquals -> NotEquals, Keywords.Assignment -> Assignment ) def floatTerm : Parser[Term] = decimalNumber ^^ { case x => FloatTerm( x.toFloat ) } def stringTerm : Parser[Term] = stringLiteral ^^ { case str => StringTerm(str) } def identifier : Parser[Term] = ident ^^ { case value => Identifier(value) } def boolTerm : Parser[Term] = (Keywords.True | Keywords.False) ^^ { case Keywords.True => TrueTerm case Keywords.False => FalseTerm } def simpleTerm : Parser[Expression] = (boolTerm | floatTerm | stringTerm) ^^ { case term => TermExp(term) } def argument = expression def arguments_aux : Parser[List[Expression]] = (argument <~ Keywords.Comma) ~ arguments ^^ { case arg ~ argList => arg :: argList } def arguments = arguments_aux | { argument ^^ { case arg => List(arg) } } def funcAppArgs : Parser[List[Expression]] = funcEmptyArgs | ( Keywords.OpenParen ~> arguments <~ Keywords.CloseParen ^^ { case args => args.foldRight(List[Expression]()) ( (a,b) => a :: b ) } ) def funcApp = identifier ~ funcAppArgs ^^ { case funcName ~ argList => FuncApp(funcName, argList) } def variableTerm : Parser[Expression] = identifier ^^ { case name => TermExp(name) } def atomic_expression = simpleTerm | funcApp | variableTerm def paren_expression : Parser[Expression] = Keywords.OpenParen ~> expression <~ Keywords.CloseParen def unary_operation : Parser[String] = Keywords.Not def unary_expression : Parser[Expression] = operation(0) ~ expression(0) ^^ { case op ~ exp => UnaryOp(keywordMap(op), exp) } def operation(precedence : Int) : Parser[String] = precedence match { case 0 => Keywords.Not case 1 => Keywords.Pow case 2 => Keywords.Times | Keywords.Divide | Keywords.And case 3 => Keywords.Plus | Keywords.Minus | Keywords.Or | Keywords.Xor case 4 => Keywords.Equals | Keywords.NotEquals case _ => throw new Exception("No operations with this precedence.") } def binary_expression(precedence : Int) : Parser[Expression] = precedence match { case 0 => throw new Exception("No operation with zero precedence.") case n => (expression (n-1)) ~ operation(n) ~ (expression (n)) ^^ { case left ~ op ~ right => BinaryOp(keywordMap(op), left, right) } } def expression(precedence : Int) : Parser[Expression] = precedence match { case 0 => unary_expression | paren_expression | atomic_expression case n => binary_expression(n) | expression(n-1) } def expression : Parser[Expression] = expression(4) def expressionStmt : Parser[Statement] = expression ^^ { case exp => ExpressionStatement(exp) } def assignment : Parser[Statement] = (identifier <~ Keywords.Assignment) ~ expression ^^ { case varName ~ exp => AssignmentVar(varName, exp) } def ifthen : Parser[Statement] = ((Keywords.If ~ Keywords.OpenParen) ~> expression <~ Keywords.CloseParen) ~ ((Keywords.Then ~ Keywords.OpenBrack) ~> statements <~ Keywords.CloseBrack) ^^ { case ifBody ~ thenBody => IfThenElse(ifBody, thenBody, Pass()) } def ifthenelse : Parser[Statement] = ((Keywords.If ~ Keywords.OpenParen) ~> expression <~ Keywords.CloseParen) ~ ((Keywords.Then ~ Keywords.OpenBrack) ~> statements <~ Keywords.CloseBrack) ~ ((Keywords.Else ~ Keywords.OpenBrack) ~> statements <~ Keywords.CloseBrack) ^^ { case ifBody ~ thenBody ~ elseBody => IfThenElse(ifBody, thenBody, elseBody) } def pass : Parser[Statement] = Keywords.Pass ^^^ { Pass() } def returnStmt : Parser[Statement] = Keywords.Return ~> expression ^^ { case exp => Return(exp) } def statement : Parser[Statement] = ((pass | returnStmt | assignment | expressionStmt) <~ Keywords.Conj) | ifthenelse | ifthen def statements_aux : Parser[Statement] = statement ~ statements ^^ { case st ~ sts => Conjunction(st, sts) } def statements : Parser[Statement] = statements_aux | statement def funcDefBody : Parser[Statement] = Keywords.OpenBrack ~> statements <~ Keywords.CloseBrack def funcEmptyArgs = Keywords.OpenParen ~ Keywords.CloseParen ^^^ { List() } def funcDefArgs : Parser[List[Term]] = funcEmptyArgs | Keywords.OpenParen ~> repsep(identifier, Keywords.Comma) <~ Keywords.CloseParen ^^ { case args => args.foldRight(List[Term]()) ( (a,b) => a :: b ) } def funcDef : Parser[Statement] = (Keywords.Define ~> identifier) ~ funcDefArgs ~ funcDefBody ^^ { case funcName ~ funcArgs ~ body => AssignmentFunc(funcName, funcArgs, body) } def funcDefAndStatement : Parser[Statement] = funcDef | statement def funcDefAndStatements_aux : Parser[Statement] = funcDefAndStatement ~ funcDefAndStatements ^^ { case stmt ~ stmts => Conjunction(stmt, stmts) } def funcDefAndStatements : Parser[Statement] = funcDefAndStatements_aux | funcDefAndStatement def parseProgram : Parser[Statement] = funcDefAndStatements def eval(input : String) = { parseAll(parseProgram, input) match { case Success(result, _) => result case Failure(m, _) => println(m) case _ => println("") } } } object Parser { def main(args : Array[String]) { val x : myParser = new myParser() println(args(0)) val lines = scala.io.Source.fromFile(args(0)).mkString println(x.eval(lines)) } } The problem is, when I run the parser on the following example it works fine: define foo(a) { if (!h(IM) && a) then { return 0; } if (a() && !h()) then { return 0; } } But when I add threes characters in the first if statement, it runs out of memory. This is absolutely blowing my mind. Can anyone help? (I suspect it has to do with repsep, but I am not sure.) define foo(a) { if (!h(IM) && a(1)) then { return 0; } if (a() && !h()) then { return 0; } } EDIT: Any constructive comments about my Scala style is also appreciated.

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Why is this class re-initialized every time?

- by pinnacler

I have 4 files and the code 'works' as expected. I try to clean everything up, place code into functions, etc... and everything looks fine... and it doesn't work. Can somebody please explain why MatLab is so quirky... or am I just stupid? Normally, I type terminator = simulation(100,20,0,0,0,1); terminator.animate(); and it should produce a map of trees with the terminator walking around in a forest. Everything rotates to his perspective. When I break it into functions... everything ceases to work. I really only changed a few lines of code, shown in comments. Code that works: classdef simulation properties landmarks robot end methods function obj = simulation(mapSize, trees, x,y,heading,velocity) obj.landmarks = landmarks(mapSize, trees); obj.robot = robot(x,y,heading,velocity); end function animate(obj) %Setup Plots fig=figure; xlabel('meters'), ylabel('meters') set(fig, 'name', 'Phil''s AWESOME 80''s Robot Simulator') xymax = obj.landmarks.mapSize*3; xymin = -(obj.landmarks.mapSize*3); l=scatter([0],[0],'bo'); axis([xymin xymax xymin xymax]); obj.landmarks.apparentPositions %Simulation Loop THIS WAS ORGANIZED for n = 1:720, %Calculate and Set Heading/Location obj.robot.headingChange = navigate(n); %Update Position obj.robot.heading = obj.robot.heading + obj.robot.headingChange; obj.landmarks.heading = obj.robot.heading; y = cosd(obj.robot.heading); x = sind(obj.robot.heading); obj.robot.x = obj.robot.x + (x*obj.robot.velocity); obj.robot.y = obj.robot.y + (y*obj.robot.velocity); obj.landmarks.x = obj.robot.x; obj.landmarks.y = obj.robot.y; %Animate set(l,'XData',obj.landmarks.apparentPositions(:,1),'YData',obj.landmarks.apparentPositions(:,2)); rectangle('Position',[-2,-2,4,4]); drawnow end end end end ----------- classdef landmarks properties fixedPositions %# positions in a fixed coordinate system. [ x, y ] mapSize = 10; %Map Size. Value is side of square x=0; y=0; heading=0; headingChange=0; end properties (Dependent) apparentPositions end methods function obj = landmarks(mapSize, numberOfTrees) obj.mapSize = mapSize; obj.fixedPositions = obj.mapSize * rand([numberOfTrees, 2]) .* sign(rand([numberOfTrees, 2]) - 0.5); end function apparent = get.apparentPositions(obj) %-STILL ROTATES AROUND ORIGINAL ORIGIN currentPosition = [obj.x ; obj.y]; apparent = bsxfun(@minus,(obj.fixedPositions)',currentPosition)'; apparent = ([cosd(obj.heading) -sind(obj.heading) ; sind(obj.heading) cosd(obj.heading)] * (apparent)')'; end end end ---------- classdef robot properties x y heading velocity headingChange end methods function obj = robot(x,y,heading,velocity) obj.x = x; obj.y = y; obj.heading = heading; obj.velocity = velocity; end end end ---------- function headingChange = navigate(n) %steeringChange = 5 * rand(1) * sign(rand(1) - 0.5); Most chaotic shit %Draw an S if n <270 headingChange=1; elseif n<540 headingChange=-1; elseif n<720 headingChange=1; else headingChange=1; end end Code that does not work... classdef simulation properties landmarks robot end methods function obj = simulation(mapSize, trees, x,y,heading,velocity) obj.landmarks = landmarks(mapSize, trees); obj.robot = robot(x,y,heading,velocity); end function animate(obj) %Setup Plots fig=figure; xlabel('meters'), ylabel('meters') set(fig, 'name', 'Phil''s AWESOME 80''s Robot Simulator') xymax = obj.landmarks.mapSize*3; xymin = -(obj.landmarks.mapSize*3); l=scatter([0],[0],'bo'); axis([xymin xymax xymin xymax]); obj.landmarks.apparentPositions %Simulation Loop for n = 1:720, %Calculate and Set Heading/Location %Update Position headingChange = navigate(n); obj.robot.updatePosition(headingChange); obj.landmarks.updatePerspective(obj.robot.heading, obj.robot.x, obj.robot.y); %Animate set(l,'XData',obj.landmarks.apparentPositions(:,1),'YData',obj.landmarks.apparentPositions(:,2)); rectangle('Position',[-2,-2,4,4]); drawnow end end end end ----------------- classdef landmarks properties fixedPositions; %# positions in a fixed coordinate system. [ x, y ] mapSize; %Map Size. Value is side of square x; y; heading; headingChange; end properties (Dependent) apparentPositions end methods function obj = createLandmarks(mapSize, numberOfTrees) obj.mapSize = mapSize; obj.fixedPositions = obj.mapSize * rand([numberOfTrees, 2]) .* sign(rand([numberOfTrees, 2]) - 0.5); end function apparent = get.apparentPositions(obj) %-STILL ROTATES AROUND ORIGINAL ORIGIN currentPosition = [obj.x ; obj.y]; apparent = bsxfun(@minus,(obj.fixedPositions)',currentPosition)'; apparent = ([cosd(obj.heading) -sind(obj.heading) ; sind(obj.heading) cosd(obj.heading)] * (apparent)')'; end function updatePerspective(obj,tempHeading,tempX,tempY) obj.heading = tempHeading; obj.x = tempX; obj.y = tempY; end end end ----------------- classdef robot properties x y heading velocity end methods function obj = robot(x,y,heading,velocity) obj.x = x; obj.y = y; obj.heading = heading; obj.velocity = velocity; end function updatePosition(obj,headingChange) obj.heading = obj.heading + headingChange; tempy = cosd(obj.heading); tempx = sind(obj.heading); obj.x = obj.x + (tempx*obj.velocity); obj.y = obj.y + (tempy*obj.velocity); end end end The navigate function is the same... I would appreciate any help as to why things aren't working. All I did was take the code from the first section from under comment: %Simulation Loop THIS WAS ORGANIZED and break it into 2 functions. One in robot and one in landmarks. Is a new instance created every time because it's constantly printing the same heading for this line int he robot class obj.heading = obj.heading + headingChange;

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li element background colors and overflow scrolling

- by user17753

I created a simple html source, and applied a small CSS style sheet to it: html { width: 100%; } body { font-family: Calibri, Tahoma, Geneva, sans-serif; padding: 20px; } pre { padding: 0; margin: 0 auto; border: 1px solid #888; font-family: Menlo,Monaco,Consolas,monospace; color: #000; width: 80%; overflow: auto; } pre li { white-space: pre; } ol { margin-top: 0; margin-bottom: 0; /* IE indents via margin-left */ color: #979797; background: #E3E3E3; } .li1 { background: #F5F5F5 } .li2 { background: #eee } I have an ordered list inside a pre-formatted tag. Every other list element is either given the class attribute li1 or li2 (the purpose of which is to alternate the colors). The list elements need the white-space: pre because the white space before and after the text node is important. The pre is to be 80% of the containing element (which ends up being 80% of the window's width). In the event of overflow in the x dimension, I want scrolling. I did all this in the above CSS, and it almost works. The issue I am having is that the background colors of the list elements don't extend with the content. They seem to be capped to the original width of the pre and/or ol element as demonstrated in the following picture where I scroll all the way right as possible: I tinkered with the CSS for a while, but I cannot determine the root cause for this or the fix. Looking for some advice on this one, thanks. Complete source with the issue is as below, NOTE: to would-be editors of the below code the pre element is intended to be on a single line as it's pre-formatted text, and formatting it otherwise would change things. <!DOCTYPE html> <html> <head> <meta http-equiv="content-type" content="text/html; charset=utf-8"> <title>Test Site</title> <style type="text/css"> html { width: 100%; } body { font-family: Calibri, Tahoma, Geneva, sans-serif; padding: 20px; } pre { padding: 0; margin: 0 auto; border: 1px solid #888; font-family: Menlo,Monaco,Consolas,monospace; color: #000; width: 80%; overflow: auto; } pre li { white-space: pre; } ol { margin-top: 0; margin-bottom: 0; /* IE indents via margin-left */ color: #979797; background: #E3E3E3; } .li1 { background: #F5F5F5 } .li2 { background: #eee } </style> </head> <body> <pre class="php"><ol><li class="li1">pre a { text-decoration: none }</li><li class="li2">pre a:hover { background: #C8C8C8 }</li><li class="li1">pre li { white-space: pre; }</li><li class="li2"> </li><li class="li1">.php ol { margin-top: 0; margin-bottom: 0; /* IE indents via margin-left */</li><li class="li2"> color: #979797; background: #E3E3E3; }</li><li class="li1"> </li><li class="li2"> </li><li class="li1"> </li><li class="li2">.php .li1 { background: #F5F5F5 }</li><li class="li1">.php .li2 { background: #eee }</li><li class="li2"> </li><li class="li1"> </li><li class="li2">.php .st0 { color: #C0C } /* string content */</li><li class="li1">.php .st_h { color: #F0C } /* string content single quoted */</li><li class="li2">.php .sy0 { color: #000 } /* semi-colon, operators */ </li><li class="li1">.php .br0 { color: #000 } /* parens */</li><li class="li2">.php .kw2 { color: #00F } /* php tags */</li><li class="li1">.php .sy1 { color: #00F } /* php tags */</li><li class="li2">.php .nu0 { color: #F00 } /* numbers */</li><li class="li1">.php .kw3 { color: #096 } /* core language functions */</li><li class="li2">.php .re0 { color: #09F; font-weight: bold; } /* variables */</li><li class="li1">.php .kw1 { color: #069; font-weight: bold; } /* control statements? */</li><li class="li2">.php .kw4 { color: #069; font-weight: bold; } /* bool? */</li><li class="li1">.php .co1 { color: #FF8400 } /* Forward slash comments */</li></ol></pre> </body> </html>

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Trying to randomise a jQuery content slider

- by alecrust

Hi everyone, I'm using a very nice jQuery content slider called Easy Slider on my site that I downloaded from Css Globe. The script is excellent and does just what I want - except I can't make it randomise the list, it always scrolls from left to right or right to left! I'm far from good with JavaScript, so my attempts at solving this have been feeble. Although I'm sure it must be an easy fix! If anyone wouldn't mind taking a glance over the script to see if they can spot what I need to change to make it random it would be greatly appreciated! I've tried contacting the original plugin developer but have had no response yet. The comments on the Easy Slider page didn't bear much fruit either unfortunately. I've pasted the script I'm using on my site below: /* * Easy Slider 1.7 - jQuery plugin * written by Alen Grakalic * http://cssglobe.com/post/4004/easy-slider-15-the-easiest-jquery-plugin-for-sliding * * Copyright (c) 2009 Alen Grakalic (http://cssglobe.com) * Dual licensed under the MIT (MIT-LICENSE.txt) * and GPL (GPL-LICENSE.txt) licenses. * * Built for jQuery library * http://jquery.com * */ (function($) { $.fn.easySlider = function(options){ // default configuration properties var defaults = { prevId: 'prevBtn', prevText: 'Previous', nextId: 'nextBtn', nextText: 'Next', controlsShow: true, controlsBefore: '', controlsAfter: '', controlsFade: true, firstId: 'firstBtn', firstText: 'First', firstShow: false, lastId: 'lastBtn', lastText: 'Last', lastShow: false, vertical: false, speed: 800, auto: false, pause: 7000, continuous: false, numeric: false, numericId: 'controls' }; var options = $.extend(defaults, options); this.each(function() { var obj = $(this); var s = $("li", obj).length; var w = $("li", obj).width(); var h = $("li", obj).height(); var clickable = true; obj.width(w); obj.height(h); obj.css("overflow","hidden"); var ts = s-1; var t = 0; $("ul", obj).css('width',s*w); if(options.continuous){ $("ul", obj).prepend($("ul li:last-child", obj).clone().css("margin-left","-"+ w +"px")); $("ul", obj).append($("ul li:nth-child(2)", obj).clone()); $("ul", obj).css('width',(s+1)*w); }; if(!options.vertical) $("li", obj).css('float','left'); if(options.controlsShow){ var html = options.controlsBefore; if(options.numeric){ html += '<ol id="'+ options.numericId +'"></ol>'; } else { if(options.firstShow) html += '<span id="'+ options.firstId +'"><a href=\"javascript:void(0);\">'+ options.firstText +'</a></span>'; html += ' <span id="'+ options.prevId +'"><a href=\"javascript:void(0);\">'+ options.prevText +'</a></span>'; html += ' <span id="'+ options.nextId +'"><a href=\"javascript:void(0);\">'+ options.nextText +'</a></span>'; if(options.lastShow) html += ' <span id="'+ options.lastId +'"><a href=\"javascript:void(0);\">'+ options.lastText +'</a></span>'; }; html += options.controlsAfter; $(obj).after(html); }; if(options.numeric){ for(var i=0;i<s;i++){ $(document.createElement("li")) .attr('id',options.numericId + (i+1)) .html('<a rel='+ i +' href=\"javascript:void(0);\">'+ (i+1) +'</a>') .appendTo($("#"+ options.numericId)) .click(function(){ animate($("a",$(this)).attr('rel'),true); }); }; } else { $("a","#"+options.nextId).click(function(){ animate("next",true); }); $("a","#"+options.prevId).click(function(){ animate("prev",true); }); $("a","#"+options.firstId).click(function(){ animate("first",true); }); $("a","#"+options.lastId).click(function(){ animate("last",true); }); }; function setCurrent(i){ i = parseInt(i)+1; $("li", "#" + options.numericId).removeClass("current"); $("li#" + options.numericId + i).addClass("current"); }; function adjust(){ if(t>ts) t=0; if(t<0) t=ts; if(!options.vertical) { $("ul",obj).css("margin-left",(t*w*-1)); } else { $("ul",obj).css("margin-left",(t*h*-1)); } clickable = true; if(options.numeric) setCurrent(t); }; function animate(dir,clicked){ if (clickable){ clickable = false; var ot = t; switch(dir){ case "next": t = (ot>=ts) ? (options.continuous ? t+1 : ts) : t+1; break; case "prev": t = (t<=0) ? (options.continuous ? t-1 : 0) : t-1; break; case "first": t = 0; break; case "last": t = ts; break; default: t = dir; break; }; var diff = Math.abs(ot-t); var speed = diff*options.speed; if(!options.vertical) { p = (t*w*-1); $("ul",obj).animate( { marginLeft: p }, { queue:false, duration:speed, complete:adjust } ); } else { p = (t*h*-1); $("ul",obj).animate( { marginTop: p }, { queue:false, duration:speed, complete:adjust } ); }; if(!options.continuous && options.controlsFade){ if(t==ts){ $("a","#"+options.nextId).hide(); $("a","#"+options.lastId).hide(); } else { $("a","#"+options.nextId).show(); $("a","#"+options.lastId).show(); }; if(t==0){ $("a","#"+options.prevId).hide(); $("a","#"+options.firstId).hide(); } else { $("a","#"+options.prevId).show(); $("a","#"+options.firstId).show(); }; }; if(clicked) clearTimeout(timeout); if(options.auto && dir=="next" && !clicked){; timeout = setTimeout(function(){ animate("next",false); },diff*options.speed+options.pause); }; }; }; // init var timeout; if(options.auto){; timeout = setTimeout(function(){ animate("next",false); },options.pause); }; if(options.numeric) setCurrent(0); if(!options.continuous && options.controlsFade){ $("a","#"+options.prevId).hide(); $("a","#"+options.firstId).hide(); }; }); }; })(jQuery); Many thanks again! Alec

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Need Help Customizing a Grammar Checking Replace Rule in Java

- by user567785

Hello, I am currently adding the Khmer (Cambodian) language to LanguageTool, an opensource grammar checker for OpenOffice (http://www.languagetool.org). I don't know enough Java to customize one of the scripts and wanted to make a request here asking if anyone would be willing to customize it for me (I can put link to your website at http://www.sbbic.org/lang/en-us/volunteer/ if you help). Here is the script that needs customization KhmerWordCoherencyRule.java: /* LanguageTool, a natural language style checker * Copyright (C) 2005 Daniel Naber (http://www.danielnaber.de) * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this library; if not, write to the Free Software * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 * USA */ package de.danielnaber.languagetool.rules.km; import java.io.BufferedReader; import java.io.IOException; import java.io.InputStream; import java.io.InputStreamReader; import java.util.ArrayList; import java.util.HashMap; import java.util.List; import java.util.Locale; import java.util.Map; import java.util.ResourceBundle; import de.danielnaber.languagetool.AnalyzedSentence; import de.danielnaber.languagetool.AnalyzedToken; import de.danielnaber.languagetool.AnalyzedTokenReadings; import de.danielnaber.languagetool.JLanguageTool; import de.danielnaber.languagetool.tools.StringTools; import de.danielnaber.languagetool.rules.Category; import de.danielnaber.languagetool.rules.RuleMatch; /** * A Khmer rule that matches words or phrases which should not be used and suggests * correct ones instead. Loads the relevant words from * <code>rules/km/coherency.txt</code>, where km is a code of the language. * * @author Andriy Rysin */ public abstract class KhmerWordCoherencyRule extends KhmerRule { private static final String FILE_ENCODING = "utf-8"; private Map<String, String> wrongWords; // e.g. "????? -> "?????" private static final String FILE_NAME = "/km/coherency.txt"; public abstract String getFileName(); public String getEncoding() { return FILE_ENCODING; } /** * Indicates if the rule is case-sensitive. Default value is <code>true</code>. * @return true if the rule is case-sensitive, false otherwise. */ //in Khmer there is no case public boolean isCaseSensitive() { return false; } /** * @return the locale used for case conversion when {@link #isCaseSensitive()} is set to <code>false</code>. */ public Locale getLocale() { return Locale.getDefault(); } public KhmerWordCoherencyRule(final ResourceBundle messages) throws IOException { if (messages != null) { super.setCategory(new Category(messages.getString("category_misc"))); } wrongWords = loadWords(JLanguageTool.getDataBroker().getFromRulesDirAsStream(getFileName())); } public String getId() { return "KM_WORD_COHERENCY"; } public String getDescription() { return "Checks for wrong words/phrases"; } public String getSuggestion() { return " does not match your previous spelling of the word, use "; } public String getShort() { return "Use a consistant spelling throughout"; } public final RuleMatch[] match(final AnalyzedSentence text) { final List<RuleMatch> ruleMatches = new ArrayList<RuleMatch>(); final AnalyzedTokenReadings[] tokens = text.getTokensWithoutWhitespace(); for (int i = 1; i < tokens.length; i++) { final String token = tokens[i].getToken(); final String origToken = token; final String replacement = isCaseSensitive()?wrongWords.get(token):wrongWords.get(token.toLowerCase(getLocale())); if (replacement != null) { final String msg = token + getSuggestion() + replacement; final int pos = tokens[i].getStartPos(); final RuleMatch potentialRuleMatch = new RuleMatch(this, pos, pos + origToken.length(), msg, getShort()); if (!isCaseSensitive() && StringTools.startsWithUppercase(token)) { potentialRuleMatch.setSuggestedReplacement(StringTools.uppercaseFirstChar(replacement)); } else { potentialRuleMatch.setSuggestedReplacement(replacement); } ruleMatches.add(potentialRuleMatch); } } return toRuleMatchArray(ruleMatches); } private Map<String, String> loadWords(final InputStream file) throws IOException { final Map<String, String> map = new HashMap<String, String>(); InputStreamReader isr = null; BufferedReader br = null; try { isr = new InputStreamReader(file, getEncoding()); br = new BufferedReader(isr); String line; while ((line = br.readLine()) != null) { line = line.trim(); if (line.length() < 1) { continue; } if (line.charAt(0) == '#') { // ignore comments continue; } final String[] parts = line.split(";"); if (parts.length != 2) { throw new IOException("Format error in file " + JLanguageTool.getDataBroker().getFromRulesDirAsUrl(getFileName()) + ", line: " + line); } map.put(parts[0], parts[1]); } } finally { if (br != null) { br.close(); } if (isr != null) { isr.close(); } } return map; } public void reset() { } } Here is what I need the SimpleReplaceRule.java to do: 1 - Be able to have more than two spelling variations in the coherency.txt file (right now it can only be Word1;Word2). 2 - Find the first use of ANY of the spelling variations in a document that are found in coherency.txt and then make sure only that spelling is used throughout the document (ex. in the coherency.txt I have Word1;Word2;Word3 then in my document on the first line I write Word2. then on next line I write Word1 and Word 3 - then the grammar checker will flag Word1 and Word3 saying that I should use the spelling "Word2" instead...etc.). If anyone can help I would be grateful! Thanks for your time, Nathan

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Ideas for multiplatform encrypted java mobile storage system

- by Fernando Miguélez

Objective I am currently designing the API for a multiplatform storage system that would offer same interface and capabilities accross following supported mobile Java Platforms: J2ME. Minimum configuration/profile CLDC 1.1/MIDP 2.0 with support for some necessary JSRs (JSR-75 for file storage). Android. No minimum platform version decided yet, but rather likely could be API level 7. Blackberry. It would use the same base source of J2ME but taking advantage of some advaced capabilities of the platform. No minimum configuration decided yet (maybe 4.6 because of 64 KB limitation for RMS on 4.5). Basically the API would sport three kind of stores: Files. These would allow standard directory/file manipulation (read/write through streams, create, mkdir, etc.). Preferences. It is a special store that handles properties accessed through keys (Similar to plain old java properties file but supporting some improvements such as different value data types such as SharedPreferences on Android platform) Local Message Queues. This store would offer basic message queue functionality. Considerations Inspired on JSR-75, all types of stores would be accessed in an uniform way by means of an URL following RFC 1738 conventions, but with custom defined prefixes (i.e. "file://" for files, "prefs://" for preferences or "queue://" for message queues). The address would refer to a virtual location that would be mapped to a physical storage object by each mobile platform implementation. Only files would allow hierarchical storage (folders) and access to external extorage memory cards (by means of a unit name, the same way as in JSR-75, but that would not change regardless of underlying platform). The other types would only support flat storage. The system should also support a secure version of all basic types. The user would indicate it by prefixing "s" to the URL (i.e. "sfile://" instead of "file://"). The API would only require one PIN (introduced only once) to access any kind of secure object types. Implementation issues For the implementation of both plaintext and encrypted stores, I would use the functionality available on the underlying platforms: Files. These are available on all platforms (J2ME only with JSR-75, but it is mandatory for our needs). The abstract File to actual File mapping is straight except for addressing issues. RMS. This type of store available on J2ME (and Blackberry) platforms is convenient for Preferences and maybe Message Queues (though depending on performance or size requirements these could be implemented by means of normal files). SharedPreferences. This type of storage, only available on Android, would match Preferences needs. SQLite databases. This could be used for message queues on Android (and maybe Blackberry). When it comes to encryption some requirements should be met: To ease the implementation it will be carried out on read/write operations basis on streams (for files), RMS Records, SharedPreferences key-value pairs, SQLite database columns. Every underlying storage object should use the same encryption key. Handling of encrypted stores should be the same as the unencrypted counterpart. The only difference (from the user point of view) accessing an encrypted store would be the addressing. The user PIN provides access to any secure storage object, but the change of it would not require to decrypt/re-encrypt all the encrypted data. Cryptographic capabilities of underlying platform should be used whenever it is possible, so we would use: J2ME: SATSA-CRYPTO if it is available (not mandatory) or lightweight BoncyCastle cryptographic framework for J2ME. Blackberry: RIM Cryptographic API or BouncyCastle Android: JCE with integraced cryptographic provider (BouncyCastle?) Doubts Having reached this point I was struck by some doubts about what solution would be more convenient, taking into account the limitation of the plataforms. These are some of my doubts: Encryption Algorithm for data. Would AES-128 be strong and fast enough? What alternatives for such scenario would you suggest? Encryption Mode. I have read about the weakness of ECB encryption versus CBC, but in this case the first would have the advantage of random access to blocks, which is interesting for seek functionality on files. What type of encryption mode would you choose instead? Is stream encryption suitable for this case? Key generation. There could be one key generated for each storage object (file, RMS RecordStore, etc.) or just use one for all the objects of the same type. The first seems "safer", though it would require some extra space on device. In your opinion what would the trade-offs of each? Key storage. For this case using a standard JKS (or PKCS#12) KeyStore file could be suited to store encryption keys, but I could also define a smaller structure (encryption-transformation / key data / checksum) that could be attached to each storage store (i.e. using addition files with the same name and special extension for plain files or embedded inside other types of objects such as RMS Record Stores). What approach would you prefer? And when it comes to using a standard KeyStore with multiple-key generation (given this is your preference), would it be better to use a record-store per storage object or just a global KeyStore keeping all keys (i.e. using the URL identifier of abstract storage object as alias)? Master key. The use of a master key seems obvious. This key should be protected by user PIN (introduced only once) and would allow access to the rest of encryption keys (they would be encrypted by means of this master key). Changing the PIN would only require to reencrypt this key and not all the encrypted data. Where would you keep it taking into account that if this got lost all data would be no further accesible? What further considerations should I take into account? Platform cryptography support. Do SATSA-CRYPTO-enabled J2ME phones really take advantage of some dedicated hardware acceleration (or other advantage I have not foreseen) and would this approach be prefered (whenever possible) over just BouncyCastle implementation? For the same reason is RIM Cryptographic API worth the license cost over BouncyCastle? Any comments, critics, further considerations or different approaches are welcome.

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Array sorting efficiency... Beginner need advice

- by SoleSoft

I'll start by saying I am very much a beginner programmer, this is essentially my first real project outside of using learning material. I've been making a 'Simon Says' style game (the game where you repeat the pattern generated by the computer) using C# and XNA, the actual game is complete and working fine but while creating it, I wanted to also create a 'top 10' scoreboard. The scoreboard would record player name, level (how many 'rounds' they've completed) and combo (how many buttons presses they got correct), the scoreboard would then be sorted by combo score. This led me to XML, the first time using it, and I eventually got to the point of having an XML file that recorded the top 10 scores. The XML file is managed within a scoreboard class, which is also responsible for adding new scores and sorting scores. Which gets me to the point... I'd like some feedback on the way I've gone about sorting the score list and how I could have done it better, I have no other way to gain feedback =(. I know .NET features Array.Sort() but I wasn't too sure of how to use it as it's not just a single array that needs to be sorted. When a new score needs to be entered into the scoreboard, the player name and level also have to be added. These are stored within an 'array of arrays' (10 = for 'top 10' scores) scoreboardComboData = new int[10]; // Combo scoreboardTextData = new string[2][]; scoreboardTextData[0] = new string[10]; // Name scoreboardTextData[1] = new string[10]; // Level as string The scoreboard class works as follows: - Checks to see if 'scoreboard.xml' exists, if not it creates it - Initialises above arrays and adds any player data from scoreboard.xml, from previous run - when AddScore(name, level, combo) is called the sort begins - Another method can also be called that populates the XML file with above array data The sort checks to see if the new score (combo) is less than or equal to any recorded scores within the scoreboardComboData array (if it's greater than a score, it moves onto the next element). If so, it moves all scores below the score it is less than or equal to down one element, essentially removing the last score and then places the new score within the element below the score it is less than or equal to. If the score is greater than all recorded scores, it moves all scores down one and inserts the new score within the first element. If it's the only score, it simply adds it to the first element. When a new score is added, the Name and Level data is also added to their relevant arrays, in the same way. What a tongue twister. Below is the AddScore method, I've added comments in the hope that it makes things clearer O_o. You can get the actual source file HERE. Below the method is an example of the quickest way to add a score to follow through with a debugger. public static void AddScore(string name, string level, int combo) { // If the scoreboard has not yet been filled, this adds another 'active' // array element each time a new score is added. The actual array size is // defined within PopulateScoreBoard() (set to 10 - for 'top 10' if (totalScores < scoreboardComboData.Length) totalScores++; // Does the scoreboard even need sorting? if (totalScores > 1) { for (int i = totalScores - 1; i > - 1; i--) { // Check to see if score (combo) is greater than score stored in // array if (combo > scoreboardComboData[i] && i != 0) { // If so continue to next element continue; } // Check to see if score (combo) is less or equal to element 'i' // score && that the element is not the last in the // array, if so the score does not need to be added to the scoreboard else if (combo <= scoreboardComboData[i] && i != scoreboardComboData.Length - 1) { // If the score is lower than element 'i' and greater than the last // element within the array, it needs to be added to the scoreboard. This is achieved // by moving each element under element 'i' down an element. The new score is then inserted // into the array under element 'i' for (int j = totalScores - 1; j > i; j--) { // Name and level data are moved down in their relevant arrays scoreboardTextData[0][j] = scoreboardTextData[0][j - 1]; scoreboardTextData[1][j] = scoreboardTextData[1][j - 1]; // Score (combo) data is moved down in relevant array scoreboardComboData[j] = scoreboardComboData[j - 1]; } // The new Name, level and score (combo) data is inserted into the relevant array under element 'i' scoreboardTextData[0][i + 1] = name; scoreboardTextData[1][i + 1] = level; scoreboardComboData[i + 1] = combo; break; } // If the method gets the this point, it means that the score is greater than all scores within // the array and therefore cannot be added in the above way. As it is not less than any score within // the array. else if (i == 0) { // All Names, levels and scores are moved down within their relevant arrays for (int j = totalScores - 1; j != 0; j--) { scoreboardTextData[0][j] = scoreboardTextData[0][j - 1]; scoreboardTextData[1][j] = scoreboardTextData[1][j - 1]; scoreboardComboData[j] = scoreboardComboData[j - 1]; } // The new number 1 top name, level and score, are added into the first element // within each of their relevant arrays. scoreboardTextData[0][0] = name; scoreboardTextData[1][0] = level; scoreboardComboData[0] = combo; break; } // If the methods get to this point, the combo score is not high enough // to be on the top10 score list and therefore needs to break break; } } // As totalScores < 1, the current score is the first to be added. Therefore no checks need to be made // and the Name, Level and combo data can be entered directly into the first element of their relevant // array. else { scoreboardTextData[0][0] = name; scoreboardTextData[1][0] = level; scoreboardComboData[0] = combo; } } } Example for adding score: private static void Initialize() { scoreboardDoc = new XmlDocument(); if (!File.Exists("Scoreboard.xml")) GenerateXML("Scoreboard.xml"); PopulateScoreBoard("Scoreboard.xml"); // ADD TEST SCORES HERE! AddScore("EXAMPLE", "10", 100); AddScore("EXAMPLE2", "24", 999); PopulateXML("Scoreboard.xml"); } In it's current state the source file is just used for testing, initialize is called within main and PopulateScoreBoard handles the majority of other initialising, so nothing else is needed, except to add a test score. I thank you for your time!

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Implementing a robust async stream reader for a console

- by Jon

I recently provided an answer to this question: C# - Realtime console output redirection. As often happens, explaining stuff (here "stuff" was how I tackled a similar problem) leads you to greater understanding and/or, as is the case here, "oops" moments. I realized that my solution, as implemented, has a bug. The bug has little practical importance, but it has an extremely large importance to me as a developer: I can't rest easy knowing that my code has the potential to blow up. Squashing the bug is the purpose of this question. I apologize for the long intro, so let's get dirty. I wanted to build a class that allows me to receive input from a Stream in an event-based manner. The stream, in my scenario, is guaranteed to be a FileStream and there is also an associated StreamReader already present to leverage. The public interface of the class is this: public class MyStreamManager { public event EventHandler<ConsoleOutputReadEventArgs> StandardOutputRead; public void StartSendingEvents(); public void StopSendingEvents(); } Obviously this specific scenario has to do with a console's standard output. StartSendingEvents and StopSendingEvents do what they advertise; for the purposes of this discussion, we can assume that events are always being sent without loss of generality. The class uses these two fields internally: protected readonly StringBuilder inputAccumulator = new StringBuilder(); protected readonly byte[] buffer = new byte[256]; The functionality of the class is implemented in the methods below. To get the ball rolling: public void StartSendingEvents(); { this.stopAutomation = false; this.BeginReadAsync(); } To read data out of the Stream without blocking, and also without requiring a carriage return char, BeginRead is called: protected void BeginReadAsync() { if (!this.stopAutomation) { this.StandardOutput.BaseStream.BeginRead( this.buffer, 0, this.buffer.Length, this.ReadHappened, null); } } The challenging part: BeginRead requires using a buffer. This means that when reading from the stream, it is possible that the bytes available to read ("incoming chunk") are larger than the buffer. Since we are only handing off data from the stream to a consumer, and that consumer may well have inside knowledge about the size and/or format of these chunks, I want to call event subscribers exactly once for each chunk. Otherwise the abstraction breaks down and the subscribers have to buffer the incoming data and reconstruct the chunks themselves using said knowledge. This is much less convenient to the calling code, and detracts from the usefulness of my class. Edit: There are comments below correctly stating that since the data is coming from a stream, there is absolutely nothing that the receiver can infer about the structure of the data unless it is fully prepared to parse it. What I am trying to do here is leverage the "flush the output" "structure" that the owner of the console imparts while writing on it. I am prepared to assume (better: allow my caller to have the option to assume) that the OS will pass me the data written between two flushes of the stream in exactly one piece. To this end, if the buffer is full after EndRead, we don't send its contents to subscribers immediately but instead append them to a StringBuilder. The contents of the StringBuilder are only sent back whenever there is no more to read from the stream (thus preserving the chunks). private void ReadHappened(IAsyncResult asyncResult) { var bytesRead = this.StandardOutput.BaseStream.EndRead(asyncResult); if (bytesRead == 0) { this.OnAutomationStopped(); return; } var input = this.StandardOutput.CurrentEncoding.GetString( this.buffer, 0, bytesRead); this.inputAccumulator.Append(input); if (bytesRead < this.buffer.Length) { this.OnInputRead(); // only send back if we 're sure we got it all } this.BeginReadAsync(); // continue "looping" with BeginRead } After any read which is not enough to fill the buffer, all accumulated data is sent to the subscribers: private void OnInputRead() { var handler = this.StandardOutputRead; if (handler == null) { return; } handler(this, new ConsoleOutputReadEventArgs(this.inputAccumulator.ToString())); this.inputAccumulator.Clear(); } (I know that as long as there are no subscribers the data gets accumulated forever. This is a deliberate decision). The good This scheme works almost perfectly: Async functionality without spawning any threads Very convenient to the calling code (just subscribe to an event) Maintains the "chunkiness" of the data; this allows the calling code to use inside knowledge of the data without doing any extra work Is almost agnostic to the buffer size (it will work correctly with any size buffer irrespective of the data being read) The bad That last almost is a very big one. Consider what happens when there is an incoming chunk with length exactly equal to the size of the buffer. The chunk will be read and buffered, but the event will not be triggered. This will be followed up by a BeginRead that expects to find more data belonging to the current chunk in order to send it back all in one piece, but... there will be no more data in the stream. In fact, as long as data is put into the stream in chunks with length exactly equal to the buffer size, the data will be buffered and the event will never be triggered. This scenario may be highly unlikely to occur in practice, especially since we can pick any number for the buffer size, but the problem is there. Solution? Unfortunately, after checking the available methods on FileStream and StreamReader, I can't find anything which lets me peek into the stream while also allowing async methods to be used on it. One "solution" would be to have a thread wait on a ManualResetEvent after the "buffer filled" condition is detected. If the event is not signaled (by the async callback) in a small amount of time, then more data from the stream will not be forthcoming and the data accumulated so far should be sent to subscribers. However, this introduces the need for another thread, requires thread synchronization, and is plain inelegant. Specifying a timeout for BeginRead would also suffice (call back into my code every now and then so I can check if there's data to be sent back; most of the time there will not be anything to do, so I expect the performance hit to be negligible). But it looks like timeouts are not supported in FileStream. Since I imagine that async calls with timeouts are an option in bare Win32, another approach might be to PInvoke the hell out of the problem. But this is also undesirable as it will introduce complexity and simply be a pain to code. Is there an elegant way to get around the problem? Thanks for being patient enough to read all of this.

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Using javascript to limit survey choices to three unique values

- by leanne

I'm required to use a limited survey application, and have to adapt the provided code to meet more advanced functionality. I need to create a weighted ranking question, so users can select their top three choices and the data will go into the survey application and be accessible in the survey reports. The application only supports 2 types of questions (text fill & multiple choice) but I can alter the code, as long as it still sends the form data back to the survey application. The code is set up so it will show a drop-down menu of 0-3 for each option. Now I want to limit the user's choices so they can only select one "1" "2" or "3", three choices total. Ideally, if the user already had "2" selected for one option and they tried to select it for another option, it would set the first "2" as "0" or blank. Is this possible to do with javascript? If so, does anyone know of a site that might show code like this, or provide similar enough examples that I could adapt it? Current code here: <html> <head><title>Survey</title></head>  <link href="---" rel="stylesheet" type="text/css"> <body bgcolor="#3c76a3">  <table border="0" align="center" cellpadding="0" cellspacing="0" style="background-attachment: scroll; background-color: #3c76a3; background-repeat: no-repeat; background-position: left top;" bgcolor="#3c76a3" topmargin="0" marginwidth="0" marginheight="0" width="100%" height="100%"> <tr> <td> <table border="0" align="center" cellpadding="0" cellspacing="0" id="survey"> <tr> <td><p> </p>  <form name="survey" action="---" method="POST"> <FONT face="Verdana, Arial, Helvetica, sans-serif"> <b>survey</b><hr>  <input type=hidden name="Buy R.J. a DeLorean_multiple_answers" value="one"> <font size=2><select name="Buy R.J. a DeLorean" SIZE=1> <option value=""> <option value="0">0 <option value="1">1 <option value="2">2 <option value="3">3 </select></font> <input type="hidden" name="Buy R.J. a DeLorean_help" value=""> <b><font size=2>Buy R.J. a DeLorean</font></b> <hr size=1>  <input type=hidden name="Fill Lisa's office with marshmallows._multiple_answers" value="one"> <font size=2><select name="Fill Lisa's office with marshmallows." SIZE=1> <option value=""> <option value="0">0 <option value="1">1 <option value="2">2 <option value="3">3 </select></font> <input type="hidden" name="Fill Lisa's office with marshmallows._help" value=""> <b><font size=2>Fill Lisa's office with marshmallows.</font></b> <hr size=1>  <input type=hidden name="Install a beer fridge in everyone's filing cabinets._multiple_answers" value="one"> <font size=2><select name="Install a beer fridge in everyone's filing cabinets." SIZE=1> <option value=""> <option value="0">0 <option value="1">1 <option value="2">2 <option value="3">3 </select></font> <input type="hidden" name="Install a beer fridge in everyone's filing cabinets._help" value=""> <b><font size=2>Install a beer fridge in everyone's filing cabinets.</font></b> <hr size=1>  <input type=hidden name="Buy a company Cessna_multiple_answers" value="one"> <font size=2><select name="Buy a company Cessna" SIZE=1> <option value=""> <option value="0">0 <option value="1">1 <option value="2">2 <option value="3">3 </select></font> <input type="hidden" name="Buy a company Cessna_help" value=""> <b><font size=2>Buy a company Cessna</font></b><br> <hr size=1>  <input type=hidden name="Replace Conf2's chairs with miniature ponies._multiple_answers" value="one"> <font size=2><select name="Replace Conf2's chairs with miniature ponies." SIZE=1> <option value=""> <option value="0">0 <option value="1">1 <option value="2">2 <option value="3">3 </select></font> <input type="hidden" name="Replace Conf2's chairs with miniature ponies._help" value=""> <b><font size=2>Replace Conf2's chairs with miniature ponies.</font></b> <hr size=1> <input type="hidden" name="question_names" value="{Buy R.J. a DeLorean} {Fill Lisa's office with marshmallows.} {Install a beer fridge in everyone's filing cabinets.} {Buy a company Cessna} {Replace Conf2's chairs with miniature ponies.}"> <p align="right"><input type="image" BORDER=0 title="Save Changes" alt="Save Changes" src="---" name="button_save_changes"> <input type="hidden" name="showconfirm" value="T"> <input type="hidden" name="showresults" value="F"> <input type="hidden" name="preventdupesmemberid" value="T"> <input type="hidden" name="preventdupesip" value="F"> <input type="hidden" name="numberquestions" value="F"> <input type="hidden" name="destinationurl" value=""> <input type="hidden" name="original_survey_id" value="62"> </form>  </td> </tr> </table> </td> </tr> </table>  </body> </html>

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Can anyone explain why my crypto++ decrypted file 16 bytes short?

- by Tom Williams

I suspect it might be too much to hope for, but can anyone with experience with crypto++ explain why the "decrypted.out" file created by main() is 16 characters short (which probably not coincidentally is the block size)? I think the issue must be in CryptStreamBuffer::GetNextChar(), but I've been staring at it and the crypto++ documentation for hours. Any other comments about how crummy or naive my std::streambuf implementation are also welcome ;-) And I've just noticed I'm missing some calls to delete so you don't have to tell me about those. Thanks, Tom // Runtime Includes #include <iostream> // Crypto++ Includes #include "aes.h" #include "modes.h" // xxx_Mode< > #include "filters.h" // StringSource and // StreamTransformation #include "files.h" using namespace std; class CryptStreamBuffer: public std::streambuf { public: CryptStreamBuffer(istream& encryptedInput, CryptoPP::StreamTransformation& c); CryptStreamBuffer(ostream& encryptedOutput, CryptoPP::StreamTransformation& c); protected: virtual int_type overflow(int_type ch = traits_type::eof()); virtual int_type uflow(); virtual int_type underflow(); virtual int_type pbackfail(int_type ch); virtual int sync(); private: int GetNextChar(); int m_NextChar; // Buffered character CryptoPP::StreamTransformationFilter* m_StreamTransformationFilter; CryptoPP::FileSource* m_Source; CryptoPP::FileSink* m_Sink; }; // class CryptStreamBuffer CryptStreamBuffer::CryptStreamBuffer(istream& encryptedInput, CryptoPP::StreamTransformation& c) : m_NextChar(traits_type::eof()), m_StreamTransformationFilter(0), m_Source(0), m_Sink(0) { m_StreamTransformationFilter = new CryptoPP::StreamTransformationFilter(c); m_Source = new CryptoPP::FileSource(encryptedInput, false, m_StreamTransformationFilter); } CryptStreamBuffer::CryptStreamBuffer(ostream& encryptedOutput, CryptoPP::StreamTransformation& c) : m_NextChar(traits_type::eof()), m_StreamTransformationFilter(0), m_Source(0), m_Sink(0) { m_Sink = new CryptoPP::FileSink(encryptedOutput); m_StreamTransformationFilter = new CryptoPP::StreamTransformationFilter(c, m_Sink); } CryptStreamBuffer::int_type CryptStreamBuffer::overflow(int_type ch) { return m_StreamTransformationFilter->Put((byte)ch); } CryptStreamBuffer::int_type CryptStreamBuffer::uflow() { int_type result = GetNextChar(); // Reset the buffered character m_NextChar = traits_type::eof(); return result; } CryptStreamBuffer::int_type CryptStreamBuffer::underflow() { return GetNextChar(); } CryptStreamBuffer::int_type CryptStreamBuffer::pbackfail(int_type ch) { return traits_type::eof(); } int CryptStreamBuffer::sync() { if (m_Sink) { m_StreamTransformationFilter->MessageEnd(); } } int CryptStreamBuffer::GetNextChar() { // If we have a buffered character do nothing if (m_NextChar != traits_type::eof()) { return m_NextChar; } // If there are no more bytes currently available then pump the source // *** I SUSPECT THE PROBLEM IS HERE *** if (m_StreamTransformationFilter->MaxRetrievable() == 0) { m_Source->Pump(1024); } // Retrieve the next byte byte nextByte; size_t noBytes = m_StreamTransformationFilter->Get(nextByte); if (0 == noBytes) { return traits_type::eof(); } // Buffer up the next character m_NextChar = nextByte; return m_NextChar; } void InitKey(byte key[]) { key[0] = -62; key[1] = 102; key[2] = 78; key[3] = 75; key[4] = -96; key[5] = 125; key[6] = 66; key[7] = 125; key[8] = -95; key[9] = -66; key[10] = 114; key[11] = 22; key[12] = 48; key[13] = 111; key[14] = -51; key[15] = 112; } void DecryptFile(const char* sourceFileName, const char* destFileName) { ifstream ifs(sourceFileName, ios::in | ios::binary); ofstream ofs(destFileName, ios::out | ios::binary); byte key[CryptoPP::AES::DEFAULT_KEYLENGTH]; InitKey(key); CryptoPP::ECB_Mode<CryptoPP::AES>::Decryption decryptor(key, sizeof(key)); if (ifs) { if (ofs) { CryptStreamBuffer cryptBuf(ifs, decryptor); std::istream decrypt(&cryptBuf); int c; while (EOF != (c = decrypt.get())) { ofs << (char)c; } ofs.flush(); } else { std::cerr << "Failed to open file '" << destFileName << "'." << endl; } } else { std::cerr << "Failed to open file '" << sourceFileName << "'." << endl; } } void EncryptFile(const char* sourceFileName, const char* destFileName) { ifstream ifs(sourceFileName, ios::in | ios::binary); ofstream ofs(destFileName, ios::out | ios::binary); byte key[CryptoPP::AES::DEFAULT_KEYLENGTH]; InitKey(key); CryptoPP::ECB_Mode<CryptoPP::AES>::Encryption encryptor(key, sizeof(key)); if (ifs) { if (ofs) { CryptStreamBuffer cryptBuf(ofs, encryptor); std::ostream encrypt(&cryptBuf); int c; while (EOF != (c = ifs.get())) { encrypt << (char)c; } encrypt.flush(); } else { std::cerr << "Failed to open file '" << destFileName << "'." << endl; } } else { std::cerr << "Failed to open file '" << sourceFileName << "'." << endl; } } int main(int argc, char* argv[]) { EncryptFile(argv[1], "encrypted.out"); DecryptFile("encrypted.out", "decrypted.out"); return 0; }

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I need help on my C++ assignment using Microsoft Visual C++

- by krayzwytie

Ok, so I don't want you to do my homework for me, but I'm a little lost with this final assignment and need all the help I can get. Learning about programming is tough enough, but doing it online is next to impossible for me... Now, to get to the program, I am going to paste what I have so far. This includes mostly //comments and what I have written so far. If you can help me figure out where all the errors are and how to complete the assignment, I will really appreciate it. Like I said, I don't want you to do my homework for me (it's my final), but any constructive criticism is welcome. This is my final assignment for this class and it is due tomorrow (Sunday before midnight, Arizona time). This is the assignment: Examine the following situation: Your company, Datamax, Inc., is in the process of automating its payroll systems. Your manager has asked you to create a program that calculates overtime pay for all employees. Your program must take into account the employee’s salary, total hours worked, and hours worked more than 40 in a week, and then provide an output that is useful and easily understood by company management. Compile your program utilizing the following background information and the code outline in Appendix D (included in the code section). Submit your project as an attachment including the code and the output. Company Background: Three employees: Mark, John, and Mary The end user needs to be prompted for three specific pieces of input—name, hours worked, and hourly wage. Calculate overtime if input is greater than 40 hours per week. Provide six test plans to verify the logic within the program. Plan 1 must display the proper information for employee #1 with overtime pay. Plan 2 must display the proper information for employee #1 with no overtime pay. Plans 3-6 are duplicates of plan 1 and 2 but for the other employees. Program Requirements: Define a base class to use for the entire program. The class holds the function calls and the variables related to the overtime pay calculations. Define one object per employee. Note there will be three employees. Your program must take the objects created and implement calculations based on total salaries, total hours, and the total number of overtime hours. See the Employee Summary Data section of the sample output. Logic Steps to Complete Your Program: Define your base class. Define your objects from your base class. Prompt for user input, updating your object classes for all three users. Implement your overtime pay calculations. Display overtime or regular time pay calculations. See the sample output below. Implement object calculations by summarizing your employee objects and display the summary information in the example below. And this is the code: // Final_Project.cpp : Defines the entry point for the console application. // #include "stdafx.h" #include <iostream> #include <string> #include <iomanip> using namespace std; // //CLASS DECLARATION SECTION // class CEmployee { public: void ImplementCalculations(string EmployeeName, double hours, double wage); void DisplayEmployInformation(void); void Addsomethingup (CEmployee, CEmployee, CEmployee); string EmployeeName ; int hours ; int overtime_hours ; int iTotal_hours ; int iTotal_OvertimeHours ; float wage ; float basepay ; float overtime_pay ; float overtime_extra ; float iTotal_salaries ; float iIndividualSalary ; }; int main() { system("cls"); cout << "Welcome to the Employee Pay Center"; /* Use this section to define your objects. You will have one object per employee. You have only three employees. The format is your class name and your object name. */ std::cout << "Please enter Employee's Name: "; std::cin >> EmployeeName; std::cout << "Please enter Total Hours for (EmployeeName): "; std::cin >> hours; std::cout << "Please enter Base Pay for(EmployeeName): "; std::cin >> basepay; /* Here you will prompt for the first employee’s information. Prompt the employee name, hours worked, and the hourly wage. For each piece of information, you will update the appropriate class member defined above. Example of Prompts Enter the employee name = Enter the hours worked = Enter his or her hourly wage = */ /* Here you will prompt for the second employee’s information. Prompt the employee name, hours worked, and the hourly wage. For each piece of information, you will update the appropriate class member defined above. Enter the employee name = Enter the hours worked = Enter his or her hourly wage = */ /* Here you will prompt for the third employee’s information. Prompt the employee name, hours worked, and the hourly wage. For each piece of information, you will update the appropriate class member defined above. Enter the employee name = Enter the hours worked = Enter his or her hourly wage = */ /* Here you will implement a function call to implement the employ calcuations for each object defined above. You will do this for each of the three employees or objects. The format for this step is the following: [(object name.function name(objectname.name, objectname.hours, objectname.wage)] ; */ /* This section you will send all three objects to a function that will add up the the following information: - Total Employee Salaries - Total Employee Hours - Total Overtime Hours The format for this function is the following: - Define a new object. - Implement function call [objectname.functionname(object name 1, object name 2, object name 3)] /* } //End of Main Function void CEmployee::ImplementCalculations (string EmployeeName, double hours, double wage){ //Initialize overtime variables overtime_hours=0; overtime_pay=0; overtime_extra=0; if (hours > 40) { /* This section is for the basic calculations for calculating overtime pay. - base pay = 40 hours times the hourly wage - overtime hours = hours worked – 40 - overtime pay = hourly wage * 1.5 - overtime extra pay over 40 = overtime hours * overtime pay - salary = overtime money over 40 hours + your base pay */ /* Implement function call to output the employee information. Function is defined below. */ } // if (hours > 40) else { /* Here you are going to calculate the hours less than 40 hours. - Your base pay is = your hours worked times your wage - Salary = your base pay */ /* Implement function call to output the employee information. Function is defined below. */ } // End of the else } //End of Primary Function void CEmployee::DisplayEmployInformation(); { // This function displays all the employee output information. /* This is your cout statements to display the employee information: Employee Name ............. = Base Pay .................. = Hours in Overtime ......... = Overtime Pay Amount........ = Total Pay ................. = */ } // END OF Display Employee Information void CEmployee::Addsomethingup (CEmployee Employ1, CEmployee Employ2) { // Adds two objects of class Employee passed as // function arguments and saves them as the calling object's data member values. /* Add the total hours for objects 1, 2, and 3. Add the salaries for each object. Add the total overtime hours. */ /* Then display the information below. %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %%%% EMPLOYEE SUMMARY DATA%%%%%%%%%%%%%%%%%%%%%%% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %%%% Total Employee Salaries ..... = 576.43 %%%% Total Employee Hours ........ = 108 %%%% Total Overtime Hours......... = 5 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% */ } // End of function

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Submit a form by code

- by user1440235

I am trying to programmatically submit a form but get an error that says: SCRIPT5007: Unable to get value of the property 'submit': object is null or undefined verify1.php, line 9 character 5 Can anyone see what I am doing wrong? Here is the code: <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>Untitled Document</title> <script type="text/javascript"> function submitform() { document.getElementById("repeatForm").submit(); } </script> </head> <body> <?php require_once('recaptchalib.php'); $privatekey = "6Ld1N9ISAAAAAB_lXt0Es0muh2cfikSgVrUP4ZXh"; $resp = recaptcha_check_answer ($privatekey, $_SERVER["REMOTE_ADDR"], $_POST["recaptcha_challenge_field"], $_POST["recaptcha_response_field"]); if (!$resp->is_valid) { // What happens when the CAPTCHA was entered incorrectly echo '<script language="JavaScript">submitform();</script>'; ; /*echo "<script>window.location.href = 'Information-Request-Voodoo-Websites.php';</script>";*/ } else { echo "<script>window.location.href = 'Confirm-Information-Request.html';</script>"; // Your code here to handle a successful verification } ?> <?php if (isset($_POST['name2'])) $_SESSION['name2'] =$_POST['name2']; if (isset($_POST['phone'])) $_SESSION['phone'] =$_POST['phone']; if (isset($_POST['email'])) $_SESSION['email'] =$_POST['email']; if (isset($_POST['company'])) $_SESSION['company'] =$_POST['company']; if (isset($_POST['pages'])) $_SESSION['pages'] =$_POST['pages']; if (isset($_POST['shopping'])) $_SESSION['shopping'] =$_POST['shopping']; if (isset($_POST['new'])) $_SESSION['new'] =$_POST['new']; if (isset($_POST['general'])) $_SESSION['general'] =$_POST['general']; if (isset($_POST['respond'])) $_SESSION['respond'] =$_POST['respond']; ?> <form id="repeatForm" action="Information-Request-Voodoo-Websites.php" method="post"> <span name="sprytextfield1"> <label for="name2">Please enter your name:</label> <input name="name" type="text" class="inputTextBoxFormat" id="name2" value="<?php echo((isset($_POST["name"]))?$_POST["name"]:"") ?>" size="30" /> <span class="textfieldRequiredMsg">A value is required.</span></span> <p><span id="sprytextfield2"> <label for="phone">Please enter your phone number:</label> <input name="phone" type="text" class="inputTextBoxFormat" id="phone" value="<?php echo((isset($_POST["phone"]))?$_POST["phone"]:"") ?>" /> <span class="textfieldRequiredMsg">A value is required.</span></span></p> <p><span id="sprytextfield3"> <label for="email">Please enter your email address:</label> <input name="email" type="text" class="inputTextBoxFormat" id="email" value="<?php echo((isset($_POST["email"]))?$_POST["email"]:"") ?>" size="40" /> <span class="textfieldRequiredMsg">A value is required.</span><span class="textfieldInvalidFormatMsg">Invalid format.</span></span></p> <p><span id="sprytextarea1"> <label for="company">Enter a brief description of your company:</label> <br /> <textarea name="company" cols="65" rows="3" class="inputTextBoxFormat" id="company"><?php echo((isset($_POST["company"]))?$_POST["company"]:"") ?></textarea> <span class="textareaRequiredMsg">A value is required.</span></span></p> <p>Anticipated number of pages:<span id="sprytextfield4"> <label for="pages"></label> <input name="pages" type="text" class="inputTextBoxFormat" id="pages" value="<?php echo((isset($_POST["pages"]))?$_POST["pages"]:"") ?>" size="7" /> <span class="textfieldRequiredMsg">A value is required.</span></span><span id="spryselect1"> <label for="shopping">Shopping cart required?</label> <select name="shopping" class="inputTextBoxFormat" id="shopping"> <option value="yes">yes</option> <option value="no">no</option> </select> <span class="selectRequiredMsg">Please select an item.</span></span></p> <p><span id="spryselect2"> <label for="new">Does this work concern a new or existing web site?</label> <select name="new" class="inputTextBoxFormat" id="new"> <option value="existing" <?php if (!(strcmp("existing", ((isset($_POST["new"]))?$_POST["new"]:"")))) {echo "selected=\"selected\"";} ?>>existing</option> <option value="new" <?php if (!(strcmp("new", ((isset($_POST["new"]))?$_POST["new"]:"")))) {echo "selected=\"selected\"";} ?>>new</option> </select> <span class="selectRequiredMsg">Please select an item.</span></span></p> <p><span id="sprytextarea2"> <label for="general">Add any additiional comments here or ask questions. </label> <textarea name="general" cols="65" rows="4" class="inputTextBoxFormat" id="general"><?php echo((isset($_POST["general"]))?$_POST["general"]:"") ?></textarea> </span></p> <p><span id="spryselect3"> <label for="respond">How would you like us to respond?</label> <select name="respond" class="inputTextBoxFormat" id="respond"> <option value="email" <?php if (!(strcmp("email", ((isset($_POST["respond"]))?$_POST["respond"]:"")))) {echo "selected=\"selected\"";} ?>>email</option> <option value="phone" <?php if (!(strcmp("phone", ((isset($_POST["respond"]))?$_POST["respond"]:"")))) {echo "selected=\"selected\"";} ?>>phone</option> </select> <input type="submit" name="formSubmit" value="Submit" /> </form> </body> </html>

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Can anyone explain why my crypto++ decrypted file is 16 bytes short?

- by Tom Williams

I suspect it might be too much to hope for, but can anyone with experience with crypto++ explain why the "decrypted.out" file created by main() is 16 characters short (which probably not coincidentally is the block size)? I think the issue must be in CryptStreamBuffer::GetNextChar(), but I've been staring at it and the crypto++ documentation for hours. Any other comments about how crummy or naive my std::streambuf implementation are also welcome ;-) And I've just noticed I'm missing some calls to delete so you don't have to tell me about those. Thanks, Tom // Runtime Includes #include <iostream> // Crypto++ Includes #include "aes.h" #include "modes.h" // xxx_Mode< > #include "filters.h" // StringSource and // StreamTransformation #include "files.h" using namespace std; class CryptStreamBuffer: public std::streambuf { public: CryptStreamBuffer(istream& encryptedInput, CryptoPP::StreamTransformation& c); CryptStreamBuffer(ostream& encryptedOutput, CryptoPP::StreamTransformation& c); protected: virtual int_type overflow(int_type ch = traits_type::eof()); virtual int_type uflow(); virtual int_type underflow(); virtual int_type pbackfail(int_type ch); virtual int sync(); private: int GetNextChar(); int m_NextChar; // Buffered character CryptoPP::StreamTransformationFilter* m_StreamTransformationFilter; CryptoPP::FileSource* m_Source; CryptoPP::FileSink* m_Sink; }; // class CryptStreamBuffer CryptStreamBuffer::CryptStreamBuffer(istream& encryptedInput, CryptoPP::StreamTransformation& c) : m_NextChar(traits_type::eof()), m_StreamTransformationFilter(0), m_Source(0), m_Sink(0) { m_StreamTransformationFilter = new CryptoPP::StreamTransformationFilter(c); m_Source = new CryptoPP::FileSource(encryptedInput, false, m_StreamTransformationFilter); } CryptStreamBuffer::CryptStreamBuffer(ostream& encryptedOutput, CryptoPP::StreamTransformation& c) : m_NextChar(traits_type::eof()), m_StreamTransformationFilter(0), m_Source(0), m_Sink(0) { m_Sink = new CryptoPP::FileSink(encryptedOutput); m_StreamTransformationFilter = new CryptoPP::StreamTransformationFilter(c, m_Sink); } CryptStreamBuffer::int_type CryptStreamBuffer::overflow(int_type ch) { return m_StreamTransformationFilter->Put((byte)ch); } CryptStreamBuffer::int_type CryptStreamBuffer::uflow() { int_type result = GetNextChar(); // Reset the buffered character m_NextChar = traits_type::eof(); return result; } CryptStreamBuffer::int_type CryptStreamBuffer::underflow() { return GetNextChar(); } CryptStreamBuffer::int_type CryptStreamBuffer::pbackfail(int_type ch) { return traits_type::eof(); } int CryptStreamBuffer::sync() { if (m_Sink) { m_StreamTransformationFilter->MessageEnd(); } } int CryptStreamBuffer::GetNextChar() { // If we have a buffered character do nothing if (m_NextChar != traits_type::eof()) { return m_NextChar; } // If there are no more bytes currently available then pump the source // *** I SUSPECT THE PROBLEM IS HERE *** if (m_StreamTransformationFilter->MaxRetrievable() == 0) { m_Source->Pump(1024); } // Retrieve the next byte byte nextByte; size_t noBytes = m_StreamTransformationFilter->Get(nextByte); if (0 == noBytes) { return traits_type::eof(); } // Buffer up the next character m_NextChar = nextByte; return m_NextChar; } void InitKey(byte key[]) { key[0] = -62; key[1] = 102; key[2] = 78; key[3] = 75; key[4] = -96; key[5] = 125; key[6] = 66; key[7] = 125; key[8] = -95; key[9] = -66; key[10] = 114; key[11] = 22; key[12] = 48; key[13] = 111; key[14] = -51; key[15] = 112; } void DecryptFile(const char* sourceFileName, const char* destFileName) { ifstream ifs(sourceFileName, ios::in | ios::binary); ofstream ofs(destFileName, ios::out | ios::binary); byte key[CryptoPP::AES::DEFAULT_KEYLENGTH]; InitKey(key); CryptoPP::ECB_Mode<CryptoPP::AES>::Decryption decryptor(key, sizeof(key)); if (ifs) { if (ofs) { CryptStreamBuffer cryptBuf(ifs, decryptor); std::istream decrypt(&cryptBuf); int c; while (EOF != (c = decrypt.get())) { ofs << (char)c; } ofs.flush(); } else { std::cerr << "Failed to open file '" << destFileName << "'." << endl; } } else { std::cerr << "Failed to open file '" << sourceFileName << "'." << endl; } } void EncryptFile(const char* sourceFileName, const char* destFileName) { ifstream ifs(sourceFileName, ios::in | ios::binary); ofstream ofs(destFileName, ios::out | ios::binary); byte key[CryptoPP::AES::DEFAULT_KEYLENGTH]; InitKey(key); CryptoPP::ECB_Mode<CryptoPP::AES>::Encryption encryptor(key, sizeof(key)); if (ifs) { if (ofs) { CryptStreamBuffer cryptBuf(ofs, encryptor); std::ostream encrypt(&cryptBuf); int c; while (EOF != (c = ifs.get())) { encrypt << (char)c; } encrypt.flush(); } else { std::cerr << "Failed to open file '" << destFileName << "'." << endl; } } else { std::cerr << "Failed to open file '" << sourceFileName << "'." << endl; } } int main(int argc, char* argv[]) { EncryptFile(argv[1], "encrypted.out"); DecryptFile("encrypted.out", "decrypted.out"); return 0; }

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php validation code format

- by user2970887

Okay I have this MySQL database form and am trying to add validation to it. After 2 days of fighting with it, I thought I would get some advice. Would like that the selected item from dropdown and Firstname, Phone, Email, are all required. Then I want to verify that the data in the Firstname, Lastname, Phone (doesn't have to be any special format), Email and Comments are all acceptable formats before putting in database. Here is what I have so far: <?php include('inc_header.php'); if(isset($_POST['add'])) { require('dbcon.php'); if(! get_magic_quotes_gpc() ) { $Id = addslashes ($_POST['Id']); $List = addslashes ($_POST['List']); $Firstname = addslashes ($_POST['Firstname']); $Lastname = addslashes ($_POST['Lastname']); $Phone = addslashes ($_POST['Phone']); $Email= addslashes ($_POST['Email']); $Calltime = addslashes ($_POST['Calltime']); $Comment = addslashes ($_POST['Comment']); } else { $Id = $_POST['Id']; $Date = $_POST['Date']; $List = $_POST['List']; $Firstname = $_POST['Firstname']; $Lastname = $_POST['Lastname']; $Phone = $_POST['Phone']; $Email = $_POST['Email']; $Calltime = $_POST['Calltime']; $Comment = $_POST['Comment']; } $error = ''; //put chosen function here function validate_Firstname($input, $pattern = "/([A-Za-z0-9])") { return !preg_match($pattern, $input); } function validate_Phone($input, $pattern = "/([A-Za-z0-9])") { return !preg_match($pattern, $input); } function isValidEmail( $Email ){ return filter_var( $Email, FILTER_VALIDATE_EMAIL ); } //get values and validate each one as required $List = mysql_real_escape_string($_POST['List']); if(!$List){ $error .= "Please choose one<br />"; } $Firstname = mysql_real_escape_string($_POST['Firstname']); if(!$Firstname){ $error .= "First name is required<br />"; } //get values and validate each one as required $Lastname = mysql_real_escape_string($_POST['Lastname']); if(!$Lastname){ $error .= "Last name is required<br />"; } //repeat for each field $Email = mysql_real_escape_string($_POST['Email']); if(!isValidEmail($Email)){ $error .= "The email entered is invalid<br />"; } //and so on... if(!$error){ //add insert into database code here $sql = "INSERT INTO contacts ". "(`Id`,`Date`,`List`,`Firstname`,`Lastname`,`Phone`,`Email`,`Calltime`,`Comment`)". "VALUES'$Id,','$Date','$List','$Firstname','$Lastname','$Phone','$Email','$Calltime','$Comment') "; mysql_select_db('hmintcwa_contacts'); $retval = mysql_query( $sql, $conn ); if(! $retval ) { die('Could not enter data: ' . mysql_error()); } echo "Entered data successfully<br /><br /><a href=contactsadd.php><font color=#000000>Back</font></a>\n"; mysql_close($conn); } else { ?> <form method="post" action="<?php echo htmlspecialchars($_SERVER["PHP_SELF"]);?>" name="ContactForm"> <table bgcolor="#000000" width="500" cellpadding="5" cellspacing="1" border="0"> <input type="hidden" name="Id" id="Id"> <tr> <td bgcolor="#e9e9e9" align="right">Requested Info</td> <td bgcolor="#ffffff" align="left"><select name="List"> <option value="0" > Please Choose One </option> <option value="Market Analysis" > Market Analysis </option> <option value="Consultation" > Consultation </option></select></td></tr> <tr> <td bgcolor="#e9e9e9" align="right">Date</td> <input name="Date" type="hidden" id="Date" value="<? print(Date("l F d, Y")); ?>" /> <td bgcolor="#ffffff" align="left"><? print(Date("l F d, Y")); ?></td> </tr> <tr> <td bgcolor="#e9e9e9" align="right">Firstname</td> <td bgcolor="#ffffff" align="left"><input name="Firstname" type="text" size="20" id="Firstname"></td></tr> <tr> <td bgcolor="#e9e9e9" align="right">Lastname</td> <td bgcolor="#ffffff" align="left"><input type="text" name="Lastname" size="20" id="Lastname"></td> </tr> <tr> <td bgcolor="#e9e9e9" align="right">Phone</td> <td bgcolor="#ffffff" align="left"><input type="text" name="Phone" size="20" id="Phone"></td></tr> <tr> <td bgcolor="#e9e9e9" align="right">Email</td> <td bgcolor="#ffffff" align="left"><input type="text" name="Email" size="20" id="Email"></td></tr> <tr> <td bgcolor="#e9e9e9" align="right">Preferred Calltime</td> <td bgcolor="#ffffff" align="left"><input type="text" name="Calltime" size="20" id="Calltime">    If none put N/A</td></tr> <tr> <td bgcolor="#e9e9e9" align="right">Comment</td> <td bgcolor="#ffffff" align="left"><textarea name="Comment" cols="40" rows="8" id="Comment"></textarea></td></tr> <tr> <td bgcolor="#e9e9e9" align="right"> </td> <td bgcolor="#ffffff" align="center"><br> <input name="add" type="submit" id="add" value="Add Contact"><input type="reset" name="Reset" value="Clear Form"><input type=button value="Cancel" onClick="history.go(-1)"><br>  </td> </tr> </table> </form> <br> </center> <?php } ?> </body> </html> So far I just keep chasing error message. Please forgive formatting I am trying to learn be gentle.

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Oddly placed CSS

- by user3682473

I want my news content to be completely centered (including image and text), but instead, it's oddly placed to the right like this: http://prntscr.com/3o7tjc I tried most ways to fix it and i can't find it... um.. here is the HTML part: <div id="mainContentContainer"> <div id="mainContent"> <div class="postTitle"> test </div> <div class="posterInfo"> <img width="40%" class="profilePic" src="/site/uploads/avatars/f3780c97491dd9f62f0dd7b1b8bb090a0b9e87d0.png"> <p>Posted by: <a class="postedBy" href="#">test</a></p> </div> <div class="postContent"> <div class="postImageContainer" align="center"> <img class="postImage" src="../uploads/img/test"> </div> <div class="post"> <p>test</p> </div> Comments have been disabled for this post.</div> </div> <div id="sidebar"> Welcome, Admin<br><a href="logout.php">Logout</a><br></div> </div> </div> annnd, here is CSS. body { margin: 0px; background-color: #6C9DDF; background-image:url("/assets/img/background.png"); background-repeat: no-repeat; } .hq { position:relative; top:40px; width:1300px; height:100%; left:1%; } #logo { position:absolute; width:40%; height:30%; right:30%; z-index: 100; } #homebtn, #playbtn, #newsbtn, #helpbtn { background: url(/assets/img/menubtns.png) no-repeat; } #homebtn { background-image: url("/assets/img/home.png"); background-repeat:no-repeat; background-size: 75%; width: 204px; height: 184px; position: absolute; top: 318px; left: 353px; } #homebtn:hover { background-image: url("/assets/img/home-rollover.png"); } #playbtn { background-image: url("/assets/img/play.png"); background-repeat:no-repeat; background-size: 100%; width: 200px; height: 230px; position: absolute; top: 240px; left: 480px; } #playbtn:hover { background-image: url("/assets/img/play-rollover.png"); } #newsbtn { background-image: url("/assets/img/news.png"); background-repeat:no-repeat; background-size: 100%; width: 290px; height: 290px; position: absolute; top: 210px; left: 650px; } #newsbtn:hover { background-image: url("/assets/img/news-rollover.png"); } #helpbtn { background-image: url("/assets/img/help.png"); background-repeat:no-repeat; background-size: 100%; width: 330px; height: 380px; position: absolute; top: 180px; left: 930px; } #helpbtn:hover { background-image: url("/assets/img/help-rollover.png"); } #mainContentContainer { border-radius: 30px 30px 30px 30px; -moz-border-radius: 30px 30px 30px 30px; -webkit-border-radius: 30px 30px 30px 30px; border: 8px solid #000000; background-color: #FFE12F; position: relative; width: 1200px; top: 60px; left: 8%; padding: 50px; overflow: hidden; height: 100%; position: relative } #mainContent { position: relative; border-radius: 30px 30px 30px 30px; -moz-border-radius: 30px 30px 30px 30px; -webkit-border-radius: 30px 30px 30px 30px; border: 0px solid #000000; background-color: #ffffff; height: 100%; padding: 20px; float: left; width: 900px; } #sidebar { position: relative; border-radius: 30px 30px 30px 30px; -moz-border-radius: 30px 30px 30px 30px; -webkit-border-radius: 30px 30px 30px 30px; border: 0px solid #000000; background-color: #ffffff; height: 100%; padding: 20px; float: right; width: 200px; } .postTitle { font-size: 40px; font-weight: bold; color: #515151; text-align: center; } .text { text-align: center; } .title { text-decoration: none; color: #515151; } .title:visited { text-decoration: none; color: #515151; } .title:hover { text-decoration: underline; } .postedBy { text-decoration: none; } .posterInfo { float: left; padding: 5px; } .postContent { overflow: hidden; } .postImageContainer { padding: 5px; } .postImage { width: 100%; position:relative; } .profilePic { border-radius: 30px 30px 30px 30px; -moz-border-radius: 30px 30px 30px 30px; -webkit-border-radius: 30px 30px 30px 30px; border: 0px solid #000000; } .registerFormWrapper { float: left; width: 50%; } .commentFormContainer { margin-top: 45px; } .commentContent { border-radius: 30px; overflow: auto; resize: none; padding: 10px; outline: none; } .commentBTN { background: url("../img/comment.png"); width: 269px; height: 260px; border: none; position: relative; top: -50px; cursor: pointer; text-indent: -999px; } .commentBTN:hover { background: url("../img/commentHover.png"); } .ToonName { font-weight: bold; font-size: 20px; } .ToonNameInput { border-radius: 30px; padding: 5px; outline: none; } .commentBTNS { outline: none; } .commentFormInputContainer { width: 60%; float: left; } .registerInput { border-radius: 30px; padding: 5px; outline: none; } .loginInput { border-radius: 30px; padding: 5px; outline: none; } .inputLabel { display: inline-block; float: left; width: 200px; font-size: 20px; font-weight: bold; } I tried changing most possible combinations, and it didnt work exactly... Here is the fiddle - http://jsfiddle.net/2EYYC/

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An Introduction to jQuery Templates

- by Stephen Walther

The goal of this blog entry is to provide you with enough information to start working with jQuery Templates. jQuery Templates enable you to display and manipulate data in the browser. For example, you can use jQuery Templates to format and display a set of database records that you have retrieved with an Ajax call. jQuery Templates supports a number of powerful features such as template tags, template composition, and wrapped templates. I’ll concentrate on the features that I think that you will find most useful. In order to focus on the jQuery Templates feature itself, this blog entry is server technology agnostic. All the samples use HTML pages instead of ASP.NET pages. In a future blog entry, I’ll focus on using jQuery Templates with ASP.NET Web Forms and ASP.NET MVC (You can do some pretty powerful things when jQuery Templates are used on the client and ASP.NET is used on the server). Introduction to jQuery Templates The jQuery Templates plugin was developed by the Microsoft ASP.NET team in collaboration with the open-source jQuery team. While working at Microsoft, I wrote the original proposal for jQuery Templates, Dave Reed wrote the original code, and Boris Moore wrote the final code. The jQuery team – especially John Resig – was very involved in each step of the process. Both the jQuery community and ASP.NET communities were very active in providing feedback. jQuery Templates will be included in the jQuery core library (the jQuery.js library) when jQuery 1.5 is released. Until jQuery 1.5 is released, you can download the jQuery Templates plugin from the jQuery Source Code Repository or you can use jQuery Templates directly from the ASP.NET CDN. The documentation for jQuery Templates is already included with the official jQuery documentation at http://api.jQuery.com. The main entry for jQuery templates is located under the topic plugins/templates. A Basic Sample of jQuery Templates Let’s start with a really simple sample of using jQuery Templates. We’ll use the plugin to display a list of books stored in a JavaScript array. Here’s the complete code: <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html > <head> <title>Intro</title> <link href="0_Site.css" rel="stylesheet" type="text/css" /> </head> <body> <div id="pageContent"> <h1>ASP.NET Bookstore</h1> <div id="bookContainer"></div> </div> <script id="bookTemplate" type="text/x-jQuery-tmpl"> <div> <img src="BookPictures/${picture}" alt="" /> <h2>${title}</h2> price: ${formatPrice(price)} </div> </script> <script type="text/javascript" src="http://ajax.aspnetcdn.com/ajax/jQuery/jquery-1.4.4.js"></script> <script type="text/javascript" src="http://ajax.aspnetcdn.com/ajax/jquery.templates/beta1/jquery.tmpl.js"></script> <script type="text/javascript"> // Create an array of books var books = [ { title: "ASP.NET 4 Unleashed", price: 37.79, picture: "AspNet4Unleashed.jpg" }, { title: "ASP.NET MVC Unleashed", price: 44.99, picture: "AspNetMvcUnleashed.jpg" }, { title: "ASP.NET Kick Start", price: 4.00, picture: "AspNetKickStart.jpg" }, { title: "ASP.NET MVC Unleashed iPhone", price: 44.99, picture: "AspNetMvcUnleashedIPhone.jpg" }, ]; // Render the books using the template $("#bookTemplate").tmpl(books).appendTo("#bookContainer"); function formatPrice(price) { return "$" + price.toFixed(2); } </script> </body> </html> When you open this page in a browser, a list of books is displayed: There are several things going on in this page which require explanation. First, notice that the page uses both the jQuery 1.4.4 and jQuery Templates libraries. Both libraries are retrieved from the ASP.NET CDN: <script type="text/javascript" src="http://ajax.aspnetcdn.com/ajax/jQuery/jquery-1.4.4.js"></script> <script type="text/javascript" src="http://ajax.aspnetcdn.com/ajax/jquery.templates/beta1/jquery.tmpl.js"></script> You can use the ASP.NET CDN for free (even for production websites). You can learn more about the files included on the ASP.NET CDN by visiting the ASP.NET CDN documentation page. Second, you should notice that the actual template is included in a script tag with a special MIME type: <script id="bookTemplate" type="text/x-jQuery-tmpl"> <div> <img src="BookPictures/${picture}" alt="" /> <h2>${title}</h2> price: ${formatPrice(price)} </div> </script> This template is displayed for each of the books rendered by the template. The template displays a book picture, title, and price. Notice that the SCRIPT tag which wraps the template has a MIME type of text/x-jQuery-tmpl. Why is the template wrapped in a SCRIPT tag and why the strange MIME type? When a browser encounters a SCRIPT tag with an unknown MIME type, it ignores the content of the tag. This is the behavior that you want with a template. You don’t want a browser to attempt to parse the contents of a template because this might cause side effects. For example, the template above includes an <img> tag with a src attribute that points at “BookPictures/${picture}”. You don’t want the browser to attempt to load an image at the URL “BookPictures/${picture}”. Instead, you want to prevent the browser from processing the IMG tag until the ${picture} expression is replaced by with the actual name of an image by the jQuery Templates plugin. If you are not worried about browser side-effects then you can wrap a template inside any HTML tag that you please. For example, the following DIV tag would also work with the jQuery Templates plugin: <div id="bookTemplate" style="display:none"> <div> <h2>${title}</h2> price: ${formatPrice(price)} </div> </div> Notice that the DIV tag includes a style=”display:none” attribute to prevent the template from being displayed until the template is parsed by the jQuery Templates plugin. Third, notice that the expression ${…} is used to display the value of a JavaScript expression within a template. For example, the expression ${title} is used to display the value of the book title property. You can use any JavaScript function that you please within the ${…} expression. For example, in the template above, the book price is formatted with the help of the custom JavaScript formatPrice() function which is defined lower in the page. Fourth, and finally, the template is rendered with the help of the tmpl() method. The following statement selects the bookTemplate and renders an array of books using the bookTemplate. The results are appended to a DIV element named bookContainer by using the standard jQuery appendTo() method. $("#bookTemplate").tmpl(books).appendTo("#bookContainer"); Using Template Tags Within a template, you can use any of the following template tags. {{tmpl}} – Used for template composition. See the section below. {{wrap}} – Used for wrapped templates. See the section below. {{each}} – Used to iterate through a collection. {{if}} – Used to conditionally display template content. {{else}} – Used with {{if}} to conditionally display template content. {{html}} – Used to display the value of an HTML expression without encoding the value. Using ${…} or {{= }} performs HTML encoding automatically. {{= }}-- Used in exactly the same way as ${…}. {{! }} – Used for displaying comments. The contents of a {{!...}} tag are ignored. For example, imagine that you want to display a list of blog entries. Each blog entry could, possibly, have an associated list of categories. The following page illustrates how you can use the { if}} and {{each}} template tags to conditionally display categories for each blog entry: <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>each</title> <link href="1_Site.css" rel="stylesheet" type="text/css" /> </head> <body> <div id="blogPostContainer"></div> <script id="blogPostTemplate" type="text/x-jQuery-tmpl"> <h1>${postTitle}</h1> <p> ${postEntry} </p> {{if categories}} Categories: {{each categories}} <i>${$value}</i> {{/each}} {{else}} Uncategorized {{/if}} </script> <script type="text/javascript" src="http://ajax.aspnetcdn.com/ajax/jQuery/jquery-1.4.4.js"></script> <script type="text/javascript" src="http://ajax.aspnetcdn.com/ajax/jquery.templates/beta1/jquery.tmpl.js"></script> <script type="text/javascript"> var blogPosts = [ { postTitle: "How to fix a sink plunger in 5 minutes", postEntry: "Lorem ipsum dolor sit amet, consectetuer adipiscing elit. Maecenas porttitor congue massa. Fusce posuere, magna sed pulvinar ultricies, purus lectus malesuada libero, sit amet commodo magna eros quis urna.", categories: ["HowTo", "Sinks", "Plumbing"] }, { postTitle: "How to remove a broken lightbulb", postEntry: "Lorem ipsum dolor sit amet, consectetuer adipiscing elit. Maecenas porttitor congue massa. Fusce posuere, magna sed pulvinar ultricies, purus lectus malesuada libero, sit amet commodo magna eros quis urna.", categories: ["HowTo", "Lightbulbs", "Electricity"] }, { postTitle: "New associate website", postEntry: "Lorem ipsum dolor sit amet, consectetuer adipiscing elit. Maecenas porttitor congue massa. Fusce posuere, magna sed pulvinar ultricies, purus lectus malesuada libero, sit amet commodo magna eros quis urna." } ]; // Render the blog posts $("#blogPostTemplate").tmpl(blogPosts).appendTo("#blogPostContainer"); </script> </body> </html> When this page is opened in a web browser, the following list of blog posts and categories is displayed: Notice that the first and second blog entries have associated categories but the third blog entry does not. The third blog entry is “Uncategorized”. The template used to render the blog entries and categories looks like this: <script id="blogPostTemplate" type="text/x-jQuery-tmpl"> <h1>${postTitle}</h1> <p> ${postEntry} </p> {{if categories}} Categories: {{each categories}} <i>${$value}</i> {{/each}} {{else}} Uncategorized {{/if}} </script> Notice the special expression $value used within the {{each}} template tag. You can use $value to display the value of the current template item. In this case, $value is used to display the value of each category in the collection of categories. Template Composition When building a fancy page, you might want to build a template out of multiple templates. In other words, you might want to take advantage of template composition. For example, imagine that you want to display a list of products. Some of the products are being sold at their normal price and some of the products are on sale. In that case, you might want to use two different templates for displaying a product: a productTemplate and a productOnSaleTemplate. The following page illustrates how you can use the {{tmpl}} tag to build a template from multiple templates: <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>Composition</title> <link href="2_Site.css" rel="stylesheet" type="text/css" /> </head> <body> <div id="pageContainer"> <h1>Products</h1> <div id="productListContainer"></div>  <script id="productListTemplate" type="text/x-jQuery-tmpl"> <div> {{if onSale}} {{tmpl "#productOnSaleTemplate"}} {{else}} {{tmpl "#productTemplate"}} {{/if}} </div> </script>  <script id="productTemplate" type="text/x-jQuery-tmpl"> ${name} </script>  <script id="productOnSaleTemplate" type="text/x-jQuery-tmpl"> <b>${name}</b> <img src="images/on_sale.png" alt="On Sale" /> </script> <script type="text/javascript" src="http://ajax.aspnetcdn.com/ajax/jQuery/jquery-1.4.4.js"></script> <script type="text/javascript" src="http://ajax.aspnetcdn.com/ajax/jquery.templates/beta1/jquery.tmpl.js"></script> <script type="text/javascript"> var products = [ { name: "Laptop", onSale: false }, { name: "Apples", onSale: true }, { name: "Comb", onSale: false } ]; $("#productListTemplate").tmpl(products).appendTo("#productListContainer"); </script> </div> </body> </html> In the page above, the main template used to display the list of products looks like this: <script id="productListTemplate" type="text/x-jQuery-tmpl"> <div> {{if onSale}} {{tmpl "#productOnSaleTemplate"}} {{else}} {{tmpl "#productTemplate"}} {{/if}} </div> </script> If a product is on sale then the product is displayed with the productOnSaleTemplate (which includes an on sale image): <script id="productOnSaleTemplate" type="text/x-jQuery-tmpl"> <b>${name}</b> <img src="images/on_sale.png" alt="On Sale" /> </script> Otherwise, the product is displayed with the normal productTemplate (which does not include the on sale image): <script id="productTemplate" type="text/x-jQuery-tmpl"> ${name} </script> You can pass a parameter to the {{tmpl}} tag. The parameter becomes the data passed to the template rendered by the {{tmpl}} tag. For example, in the previous section, we used the {{each}} template tag to display a list of categories for each blog entry like this: <script id="blogPostTemplate" type="text/x-jQuery-tmpl"> <h1>${postTitle}</h1> <p> ${postEntry} </p> {{if categories}} Categories: {{each categories}} <i>${$value}</i> {{/each}} {{else}} Uncategorized {{/if}} </script> Another way to create this template is to use template composition like this: <script id="blogPostTemplate" type="text/x-jQuery-tmpl"> <h1>${postTitle}</h1> <p> ${postEntry} </p> {{if categories}} Categories: {{tmpl(categories) "#categoryTemplate"}} {{else}} Uncategorized {{/if}} </script> <script id="categoryTemplate" type="text/x-jQuery-tmpl"> <i>${$data}</i>   </script> Using the {{each}} tag or {{tmpl}} tag is largely a matter of personal preference. Wrapped Templates The {{wrap}} template tag enables you to take a chunk of HTML and transform the HTML into another chunk of HTML (think easy XSLT). When you use the {{wrap}} tag, you work with two templates. The first template contains the HTML being transformed and the second template includes the filter expressions for transforming the HTML. For example, you can use the {{wrap}} template tag to transform a chunk of HTML into an interactive tab strip: When you click any of the tabs, you see the corresponding content. This tab strip was created with the following page: <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>Wrapped Templates</title> <style type="text/css"> body { font-family: Arial; background-color:black; } .tabs div { display:inline-block; border-bottom: 1px solid black; padding:4px; background-color:gray; cursor:pointer; } .tabs div.tabState_true { background-color:white; border-bottom:1px solid white; } .tabBody { border-top:1px solid white; padding:10px; background-color:white; min-height:400px; width:400px; } </style> </head> <body> <div id="tabsView"></div> <script id="tabsContent" type="text/x-jquery-tmpl"> {{wrap "#tabsWrap"}} <h3>Tab 1</h3> <div> Content of tab 1. Lorem ipsum dolor <b>sit</b> amet, consectetuer adipiscing elit. Maecenas porttitor congue massa. Fusce posuere, magna sed pulvinar ultricies, purus lectus malesuada libero, sit amet commodo magna eros quis urna. </div> <h3>Tab 2</h3> <div> Content of tab 2. Lorem ipsum dolor <b>sit</b> amet, consectetuer adipiscing elit. Maecenas porttitor congue massa. Fusce posuere, magna sed pulvinar ultricies, purus lectus malesuada libero, sit amet commodo magna eros quis urna. </div> <h3>Tab 3</h3> <div> Content of tab 3. Lorem ipsum dolor <b>sit</b> amet, consectetuer adipiscing elit. Maecenas porttitor congue massa. Fusce posuere, magna sed pulvinar ultricies, purus lectus malesuada libero, sit amet commodo magna eros quis urna. </div> {{/wrap}} </script> <script id="tabsWrap" type="text/x-jquery-tmpl"> <div class="tabs"> {{each $item.html("h3", true)}} <div class="tabState_${$index === selectedTabIndex}"> ${$value} </div> {{/each}} </div> <div class="tabBody"> {{html $item.html("div")[selectedTabIndex]}} </div> </script> <script type="text/javascript" src="http://ajax.aspnetcdn.com/ajax/jQuery/jquery-1.4.4.js"></script> <script type="text/javascript" src="http://ajax.aspnetcdn.com/ajax/jquery.templates/beta1/jquery.tmpl.js"></script> <script type="text/javascript"> // Global for tracking selected tab var selectedTabIndex = 0; // Render the tab strip $("#tabsContent").tmpl().appendTo("#tabsView"); // When a tab is clicked, update the tab strip $("#tabsView") .delegate(".tabState_false", "click", function () { var templateItem = $.tmplItem(this); selectedTabIndex = $(this).index(); templateItem.update(); }); </script> </body> </html> The “source” for the tab strip is contained in the following template: <script id="tabsContent" type="text/x-jquery-tmpl"> {{wrap "#tabsWrap"}} <h3>Tab 1</h3> <div> Content of tab 1. Lorem ipsum dolor <b>sit</b> amet, consectetuer adipiscing elit. Maecenas porttitor congue massa. Fusce posuere, magna sed pulvinar ultricies, purus lectus malesuada libero, sit amet commodo magna eros quis urna. </div> <h3>Tab 2</h3> <div> Content of tab 2. Lorem ipsum dolor <b>sit</b> amet, consectetuer adipiscing elit. Maecenas porttitor congue massa. Fusce posuere, magna sed pulvinar ultricies, purus lectus malesuada libero, sit amet commodo magna eros quis urna. </div> <h3>Tab 3</h3> <div> Content of tab 3. Lorem ipsum dolor <b>sit</b> amet, consectetuer adipiscing elit. Maecenas porttitor congue massa. Fusce posuere, magna sed pulvinar ultricies, purus lectus malesuada libero, sit amet commodo magna eros quis urna. </div> {{/wrap}} </script> The tab strip is created with a list of H3 elements (which represent each tab) and DIV elements (which represent the body of each tab). Notice that the HTML content is wrapped in the {{wrap}} template tag. This template tag points at the following tabsWrap template: <script id="tabsWrap" type="text/x-jquery-tmpl"> <div class="tabs"> {{each $item.html("h3", true)}} <div class="tabState_${$index === selectedTabIndex}"> ${$value} </div> {{/each}} </div> <div class="tabBody"> {{html $item.html("div")[selectedTabIndex]}} </div> </script> The tabs DIV contains all of the tabs. The {{each}} template tag is used to loop through each of the H3 elements from the source template and render a DIV tag that represents a particular tab. The template item html() method is used to filter content from the “source” HTML template. The html() method accepts a jQuery selector for its first parameter. The tabs are retrieved from the source template by using an h3 filter. The second parameter passed to the html() method – the textOnly parameter -- causes the filter to return the inner text of each h3 element. You can learn more about the html() method at the jQuery website (see the section on $item.html()). The tabBody DIV renders the body of the selected tab. Notice that the {{html}} template tag is used to display the tab body so that HTML content in the body won’t be HTML encoded. The html() method is used, once again, to grab all of the DIV elements from the source HTML template. The selectedTabIndex global variable is used to display the contents of the selected tab. Remote Templates A common feature request for jQuery templates is support for remote templates. Developers want to be able to separate templates into different files. Adding support for remote templates requires only a few lines of extra code (Dave Ward has a nice blog entry on this). For example, the following page uses a remote template from a file named BookTemplate.htm: <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>Remote Templates</title> <link href="0_Site.css" rel="stylesheet" type="text/css" /> </head> <body> <div id="pageContent"> <h1>ASP.NET Bookstore</h1> <div id="bookContainer"></div> </div> <script type="text/javascript" src="http://ajax.aspnetcdn.com/ajax/jQuery/jquery-1.4.4.js"></script> <script type="text/javascript" src="http://ajax.aspnetcdn.com/ajax/jquery.templates/beta1/jquery.tmpl.js"></script> <script type="text/javascript"> // Create an array of books var books = [ { title: "ASP.NET 4 Unleashed", price: 37.79, picture: "AspNet4Unleashed.jpg" }, { title: "ASP.NET MVC Unleashed", price: 44.99, picture: "AspNetMvcUnleashed.jpg" }, { title: "ASP.NET Kick Start", price: 4.00, picture: "AspNetKickStart.jpg" }, { title: "ASP.NET MVC Unleashed iPhone", price: 44.99, picture: "AspNetMvcUnleashedIPhone.jpg" }, ]; // Get the remote template $.get("BookTemplate.htm", null, function (bookTemplate) { // Render the books using the remote template $.tmpl(bookTemplate, books).appendTo("#bookContainer"); }); function formatPrice(price) { return "$" + price.toFixed(2); } </script> </body> </html> The remote template is retrieved (and rendered) with the following code: // Get the remote template $.get("BookTemplate.htm", null, function (bookTemplate) { // Render the books using the remote template $.tmpl(bookTemplate, books).appendTo("#bookContainer"); }); This code uses the standard jQuery $.get() method to get the BookTemplate.htm file from the server with an Ajax request. After the BookTemplate.htm file is successfully retrieved, the $.tmpl() method is used to render an array of books with the template. Here’s what the BookTemplate.htm file looks like: <div> <img src="BookPictures/${picture}" alt="" /> <h2>${title}</h2> price: ${formatPrice(price)} </div> Notice that the template in the BooksTemplate.htm file is not wrapped by a SCRIPT element. There is no need to wrap the template in this case because there is no possibility that the template will get interpreted before you want it to be interpreted. If you plan to use the bookTemplate multiple times – for example, you are paging or sorting the books -- then you should compile the template into a function and cache the compiled template function. For example, the following page can be used to page through a list of 100 products (using iPhone style More paging). <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>Template Caching</title> <link href="6_Site.css" rel="stylesheet" type="text/css" /> </head> <body> <h1>Products</h1> <div id="productContainer"></div> <button id="more">More</button> <script type="text/javascript" src="http://ajax.aspnetcdn.com/ajax/jQuery/jquery-1.4.4.js"></script> <script type="text/javascript" src="http://ajax.aspnetcdn.com/ajax/jquery.templates/beta1/jquery.tmpl.js"></script> <script type="text/javascript"> // Globals var pageIndex = 0; // Create an array of products var products = []; for (var i = 0; i < 100; i++) { products.push({ name: "Product " + (i + 1) }); } // Get the remote template $.get("ProductTemplate.htm", null, function (productTemplate) { // Compile and cache the template $.template("productTemplate", productTemplate); // Render the products renderProducts(0); }); $("#more").click(function () { pageIndex++; renderProducts(); }); function renderProducts() { // Get page of products var pageOfProducts = products.slice(pageIndex * 5, pageIndex * 5 + 5); // Used cached productTemplate to render products $.tmpl("productTemplate", pageOfProducts).appendTo("#productContainer"); } function formatPrice(price) { return "$" + price.toFixed(2); } </script> </body> </html> The ProductTemplate is retrieved from an external file named ProductTemplate.htm. This template is retrieved only once. Furthermore, it is compiled and cached with the help of the $.template() method: // Get the remote template $.get("ProductTemplate.htm", null, function (productTemplate) { // Compile and cache the template $.template("productTemplate", productTemplate); // Render the products renderProducts(0); }); The $.template() method compiles the HTML representation of the template into a JavaScript function and caches the template function with the name productTemplate. The cached template can be used by calling the $.tmp() method. The productTemplate is used in the renderProducts() method: function renderProducts() { // Get page of products var pageOfProducts = products.slice(pageIndex * 5, pageIndex * 5 + 5); // Used cached productTemplate to render products $.tmpl("productTemplate", pageOfProducts).appendTo("#productContainer"); } In the code above, the first parameter passed to the $.tmpl() method is the name of a cached template. Working with Template Items In this final section, I want to devote some space to discussing Template Items. A new Template Item is created for each rendered instance of a template. For example, if you are displaying a list of 100 products with a template, then 100 Template Items are created. A Template Item has the following properties and methods: data – The data associated with the Template Instance. For example, a product. tmpl – The template associated with the Template Instance. parent – The parent template item if the template is nested. nodes – The HTML content of the template. calls – Used by {{wrap}} template tag. nest – Used by {{tmpl}} template tag. wrap – Used to imperatively enable wrapped templates. html – Used to filter content from a wrapped template. See the above section on wrapped templates. update – Used to re-render a template item. The last method – the update() method -- is especially interesting because it enables you to re-render a template item with new data or even a new template. For example, the following page displays a list of books. When you hover your mouse over any of the books, additional book details are displayed. In the following screenshot, details for ASP.NET Kick Start are displayed. <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>Template Item</title> <link href="0_Site.css" rel="stylesheet" type="text/css" /> </head> <body> <div id="pageContent"> <h1>ASP.NET Bookstore</h1> <div id="bookContainer"></div> </div> <script id="bookTemplate" type="text/x-jQuery-tmpl"> <div class="bookItem"> <img src="BookPictures/${picture}" alt="" /> <h2>${title}</h2> price: ${formatPrice(price)} </div> </script> <script id="bookDetailsTemplate" type="text/x-jQuery-tmpl"> <div class="bookItem"> <img src="BookPictures/${picture}" alt="" /> <h2>${title}</h2> price: ${formatPrice(price)} <p> ${description} </p> </div> </script> <script type="text/javascript" src="http://ajax.aspnetcdn.com/ajax/jQuery/jquery-1.4.4.js"></script> <script type="text/javascript" src="http://ajax.aspnetcdn.com/ajax/jquery.templates/beta1/jquery.tmpl.js"></script> <script type="text/javascript"> // Create an array of books var books = [ { title: "ASP.NET 4 Unleashed", price: 37.79, picture: "AspNet4Unleashed.jpg", description: "The most comprehensive book on Microsoft’s new ASP.NET 4.. " }, { title: "ASP.NET MVC Unleashed", price: 44.99, picture: "AspNetMvcUnleashed.jpg", description: "Writing for professional programmers, Walther explains the crucial concepts that make the Model-View-Controller (MVC) development paradigm work…" }, { title: "ASP.NET Kick Start", price: 4.00, picture: "AspNetKickStart.jpg", description: "Visual Studio .NET is the premier development environment for creating .NET applications…." }, { title: "ASP.NET MVC Unleashed iPhone", price: 44.99, picture: "AspNetMvcUnleashedIPhone.jpg", description: "ASP.NET MVC Unleashed for the iPhone…" }, ]; // Render the books using the template $("#bookTemplate").tmpl(books).appendTo("#bookContainer"); // Get compiled details template var bookDetailsTemplate = $("#bookDetailsTemplate").template(); // Add hover handler $(".bookItem").mouseenter(function () { // Get template item associated with DIV var templateItem = $(this).tmplItem(); // Change template to compiled template templateItem.tmpl = bookDetailsTemplate; // Re-render template templateItem.update(); }); function formatPrice(price) { return "$" + price.toFixed(2); } </script> </body> </html> There are two templates used to display a book: bookTemplate and bookDetailsTemplate. When you hover your mouse over a template item, the standard bookTemplate is swapped out for the bookDetailsTemplate. The bookDetailsTemplate displays a book description. The books are rendered with the bookTemplate with the following line of code: // Render the books using the template $("#bookTemplate").tmpl(books).appendTo("#bookContainer"); The following code is used to swap the bookTemplate and the bookDetailsTemplate to show details for a book: // Get compiled details template var bookDetailsTemplate = $("#bookDetailsTemplate").template(); // Add hover handler $(".bookItem").mouseenter(function () { // Get template item associated with DIV var templateItem = $(this).tmplItem(); // Change template to compiled template templateItem.tmpl = bookDetailsTemplate; // Re-render template templateItem.update(); }); When you hover your mouse over a DIV element rendered by the bookTemplate, the mouseenter handler executes. First, this handler retrieves the Template Item associated with the DIV element by calling the tmplItem() method. The tmplItem() method returns a Template Item. Next, a new template is assigned to the Template Item. Notice that a compiled version of the bookDetailsTemplate is assigned to the Template Item’s tmpl property. The template is compiled earlier in the code by calling the template() method. Finally, the Template Item update() method is called to re-render the Template Item with the bookDetailsTemplate instead of the original bookTemplate. Summary This is a long blog entry and I still have not managed to cover all of the features of jQuery Templates J However, I’ve tried to cover the most important features of jQuery Templates such as template composition, template wrapping, and template items. To learn more about jQuery Templates, I recommend that you look at the documentation for jQuery Templates at the official jQuery website. Another great way to learn more about jQuery Templates is to look at the (unminified) source code.

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What's New in ASP.NET 4

- by Navaneeth

The .NET Framework version 4 includes enhancements for ASP.NET 4 in targeted areas. Visual Studio 2010 and Microsoft Visual Web Developer Express also include enhancements and new features for improved Web development. This document provides an overview of many of the new features that are included in the upcoming release. This topic contains the following sections: ASP.NET Core Services ASP.NET Web Forms ASP.NET MVC Dynamic Data ASP.NET Chart Control Visual Web Developer Enhancements Web Application Deployment with Visual Studio 2010 Enhancements to ASP.NET Multi-Targeting ASP.NET Core Services ASP.NET 4 introduces many features that improve core ASP.NET services such as output caching and session state storage. Extensible Output Caching Since the time that ASP.NET 1.0 was released, output caching has enabled developers to store the generated output of pages, controls, and HTTP responses in memory. On subsequent Web requests, ASP.NET can serve content more quickly by retrieving the generated output from memory instead of regenerating the output from scratch. However, this approach has a limitation — generated content always has to be stored in memory. On servers that experience heavy traffic, the memory requirements for output caching can compete with memory requirements for other parts of a Web application. ASP.NET 4 adds extensibility to output caching that enables you to configure one or more custom output-cache providers. Output-cache providers can use any storage mechanism to persist HTML content. These storage options can include local or remote disks, cloud storage, and distributed cache engines. Output-cache provider extensibility in ASP.NET 4 lets you design more aggressive and more intelligent output-caching strategies for Web sites. For example, you can create an output-cache provider that caches the "Top 10" pages of a site in memory, while caching pages that get lower traffic on disk. Alternatively, you can cache every vary-by combination for a rendered page, but use a distributed cache so that the memory consumption is offloaded from front-end Web servers. You create a custom output-cache provider as a class that derives from the OutputCacheProvider type. You can then configure the provider in the Web.config file by using the new providers subsection of the outputCache element For more information and for examples that show how to configure the output cache, see outputCache Element for caching (ASP.NET Settings Schema). For more information about the classes that support caching, see the documentation for the OutputCache and OutputCacheProvider classes. By default, in ASP.NET 4, all HTTP responses, rendered pages, and controls use the in-memory output cache. The defaultProvider attribute for ASP.NET is AspNetInternalProvider. You can change the default output-cache provider used for a Web application by specifying a different provider name for defaultProvider attribute. In addition, you can select different output-cache providers for individual control and for individual requests and programmatically specify which provider to use. For more information, see the HttpApplication.GetOutputCacheProviderName(HttpContext) method. The easiest way to choose a different output-cache provider for different Web user controls is to do so declaratively by using the new providerName attribute in a page or control directive, as shown in the following example: <%@ OutputCache Duration="60" VaryByParam="None" providerName="DiskCache" %> Preloading Web Applications Some Web applications must load large amounts of data or must perform expensive initialization processing before serving the first request. In earlier versions of ASP.NET, for these situations you had to devise custom approaches to "wake up" an ASP.NET application and then run initialization code during the Application_Load method in the Global.asax file. To address this scenario, a new application preload manager (autostart feature) is available when ASP.NET 4 runs on IIS 7.5 on Windows Server 2008 R2. The preload feature provides a controlled approach for starting up an application pool, initializing an ASP.NET application, and then accepting HTTP requests. It lets you perform expensive application initialization prior to processing the first HTTP request. For example, you can use the application preload manager to initialize an application and then signal a load-balancer that the application was initialized and ready to accept HTTP traffic. To use the application preload manager, an IIS administrator sets an application pool in IIS 7.5 to be automatically started by using the following configuration in the applicationHost.config file: <applicationPools> <add name="MyApplicationPool" startMode="AlwaysRunning" /> </applicationPools> Because a single application pool can contain multiple applications, you specify individual applications to be automatically started by using the following configuration in the applicationHost.config file: <sites> <site name="MySite" id="1"> <application path="/" serviceAutoStartEnabled="true" serviceAutoStartProvider="PrewarmMyCache" >  </application> </site> </sites>  <serviceAutoStartProviders> <add name="PrewarmMyCache" type="MyNamespace.CustomInitialization, MyLibrary" /> </serviceAutoStartProviders> When an IIS 7.5 server is cold-started or when an individual application pool is recycled, IIS 7.5 uses the information in the applicationHost.config file to determine which Web applications have to be automatically started. For each application that is marked for preload, IIS7.5 sends a request to ASP.NET 4 to start the application in a state during which the application temporarily does not accept HTTP requests. When it is in this state, ASP.NET instantiates the type defined by the serviceAutoStartProvider attribute (as shown in the previous example) and calls into its public entry point. You create a managed preload type that has the required entry point by implementing the IProcessHostPreloadClient interface, as shown in the following example: public class CustomInitialization : System.Web.Hosting.IProcessHostPreloadClient { public void Preload(string[] parameters) { // Perform initialization. } } After your initialization code runs in the Preload method and after the method returns, the ASP.NET application is ready to process requests. Permanently Redirecting a Page Content in Web applications is often moved over the lifetime of the application. This can lead to links to be out of date, such as the links that are returned by search engines. In ASP.NET, developers have traditionally handled requests to old URLs by using the Redirect method to forward a request to the new URL. However, the Redirect method issues an HTTP 302 (Found) response (which is used for a temporary redirect). This results in an extra HTTP round trip. ASP.NET 4 adds a RedirectPermanent helper method that makes it easy to issue HTTP 301 (Moved Permanently) responses, as in the following example: RedirectPermanent("/newpath/foroldcontent.aspx"); Search engines and other user agents that recognize permanent redirects will store the new URL that is associated with the content, which eliminates the unnecessary round trip made by the browser for temporary redirects. Session State Compression By default, ASP.NET provides two options for storing session state across a Web farm. The first option is a session state provider that invokes an out-of-process session state server. The second option is a session state provider that stores data in a Microsoft SQL Server database. Because both options store state information outside a Web application's worker process, session state has to be serialized before it is sent to remote storage. If a large amount of data is saved in session state, the size of the serialized data can become very large. ASP.NET 4 introduces a new compression option for both kinds of out-of-process session state providers. By using this option, applications that have spare CPU cycles on Web servers can achieve substantial reductions in the size of serialized session state data. You can set this option using the new compressionEnabled attribute of the sessionState element in the configuration file. When the compressionEnabled configuration option is set to true, ASP.NET compresses (and decompresses) serialized session state by using the .NET Framework GZipStreamclass. The following example shows how to set this attribute. <sessionState mode="SqlServer" sqlConnectionString="data source=dbserver;Initial Catalog=aspnetstate" allowCustomSqlDatabase="true" compressionEnabled="true" /> ASP.NET Web Forms Web Forms has been a core feature in ASP.NET since the release of ASP.NET 1.0. Many enhancements have been in this area for ASP.NET 4, such as the following: The ability to set meta tags. More control over view state. Support for recently introduced browsers and devices. Easier ways to work with browser capabilities. Support for using ASP.NET routing with Web Forms. More control over generated IDs. The ability to persist selected rows in data controls. More control over rendered HTML in the FormView and ListView controls. Filtering support for data source controls. Enhanced support for Web standards and accessibility Setting Meta Tags with the Page.MetaKeywords and Page.MetaDescription Properties Two properties have been added to the Page class: MetaKeywords and MetaDescription. These two properties represent corresponding meta tags in the HTML rendered for a page, as shown in the following example: <head id="Head1" runat="server"> <title>Untitled Page</title> <meta name="keywords" content="keyword1, keyword2' /> <meta name="description" content="Description of my page" /> </head> These two properties work like the Title property does, and they can be set in the @ Page directive. For more information, see Page.MetaKeywords and Page.MetaDescription. Enabling View State for Individual Controls A new property has been added to the Control class: ViewStateMode. You can use this property to disable view state for all controls on a page except those for which you explicitly enable view state. View state data is included in a page's HTML and increases the amount of time it takes to send a page to the client and post it back. Storing more view state than is necessary can cause significant decrease in performance. In earlier versions of ASP.NET, you could reduce the impact of view state on a page's performance by disabling view state for specific controls. But sometimes it is easier to enable view state for a few controls that need it instead of disabling it for many that do not need it. For more information, see Control.ViewStateMode. Support for Recently Introduced Browsers and Devices ASP.NET includes a feature that is named browser capabilities that lets you determine the capabilities of the browser that a user is using. Browser capabilities are represented by the HttpBrowserCapabilities object which is stored in the HttpRequest.Browser property. Information about a particular browser's capabilities is defined by a browser definition file. In ASP.NET 4, these browser definition files have been updated to contain information about recently introduced browsers and devices such as Google Chrome, Research in Motion BlackBerry smart phones, and Apple iPhone. Existing browser definition files have also been updated. For more information, see How to: Upgrade an ASP.NET Web Application to ASP.NET 4 and ASP.NET Web Server Controls and Browser Capabilities. The browser definition files that are included with ASP.NET 4 are shown in the following list: •blackberry.browser •chrome.browser •Default.browser •firefox.browser •gateway.browser •generic.browser •ie.browser •iemobile.browser •iphone.browser •opera.browser •safari.browser A New Way to Define Browser Capabilities ASP.NET 4 includes a new feature referred to as browser capabilities providers. As the name suggests, this lets you build a provider that in turn lets you write custom code to determine browser capabilities. In ASP.NET version 3.5 Service Pack 1, you define browser capabilities in an XML file. This file resides in a machine-level folder or an application-level folder. Most developers do not need to customize these files, but for those who do, the provider approach can be easier than dealing with complex XML syntax. The provider approach makes it possible to simplify the process by implementing a common browser definition syntax, or a database that contains up-to-date browser definitions, or even a Web service for such a database. For more information about the new browser capabilities provider, see the What's New for ASP.NET 4 White Paper. Routing in ASP.NET 4 ASP.NET 4 adds built-in support for routing with Web Forms. Routing is a feature that was introduced with ASP.NET 3.5 SP1 and lets you configure an application to use URLs that are meaningful to users and to search engines because they do not have to specify physical file names. This can make your site more user-friendly and your site content more discoverable by search engines. For example, the URL for a page that displays product categories in your application might look like the following example: http://website/products.aspx?categoryid=12 By using routing, you can use the following URL to render the same information: http://website/products/software The second URL lets the user know what to expect and can result in significantly improved rankings in search engine results. the new features include the following: The PageRouteHandler class is a simple HTTP handler that you use when you define routes. You no longer have to write a custom route handler. The HttpRequest.RequestContext and Page.RouteData properties make it easier to access information that is passed in URL parameters. The RouteUrl expression provides a simple way to create a routed URL in markup. The RouteValue expression provides a simple way to extract URL parameter values in markup. The RouteParameter class makes it easier to pass URL parameter values to a query for a data source control (similar to FormParameter). You no longer have to change the Web.config file to enable routing. For more information about routing, see the following topics: ASP.NET Routing Walkthrough: Using ASP.NET Routing in a Web Forms Application How to: Define Routes for Web Forms Applications How to: Construct URLs from Routes How to: Access URL Parameters in a Routed Page Setting Client IDs The new ClientIDMode property makes it easier to write client script that references HTML elements rendered for server controls. Increasing use of Microsoft Ajax makes the need to do this more common. For example, you may have a data control that renders a long list of products with prices and you want to use client script to make a Web service call and update individual prices in the list as they change without refreshing the entire page. Typically you get a reference to an HTML element in client script by using the document.GetElementById method. You pass to this method the value of the id attribute of the HTML element you want to reference. In the case of elements that are rendered for ASP.NET server controls earlier versions of ASP.NET could make this difficult or impossible. You were not always able to predict what id values ASP.NET would generate, or ASP.NET could generate very long id values. The problem was especially difficult for data controls that would generate multiple rows for a single instance of the control in your markup. ASP.NET 4 adds two new algorithms for generating id attributes. These algorithms can generate id attributes that are easier to work with in client script because they are more predictable and that are easier to work with because they are simpler. For more information about how to use the new algorithms, see the following topics: ASP.NET Web Server Control Identification Walkthrough: Making Data-Bound Controls Easier to Access from JavaScript Walkthrough: Making Controls Located in Web User Controls Easier to Access from JavaScript How to: Access Controls from JavaScript by ID Persisting Row Selection in Data Controls The GridView and ListView controls enable users to select a row. In previous versions of ASP.NET, row selection was based on the row index on the page. For example, if you select the third item on page 1 and then move to page 2, the third item on page 2 is selected. In most cases, is more desirable not to select any rows on page 2. ASP.NET 4 supports Persisted Selection, a new feature that was initially supported only in Dynamic Data projects in the .NET Framework 3.5 SP1. When this feature is enabled, the selected item is based on the row data key. This means that if you select the third row on page 1 and move to page 2, nothing is selected on page 2. When you move back to page 1, the third row is still selected. This is a much more natural behavior than the behavior in earlier versions of ASP.NET. Persisted selection is now supported for the GridView and ListView controls in all projects. You can enable this feature in the GridView control, for example, by setting the EnablePersistedSelection property, as shown in the following example: <asp:GridView id="GridView2" runat="server" PersistedSelection="true"> </asp:GridView> FormView Control Enhancements The FormView control is enhanced to make it easier to style the content of the control with CSS. In previous versions of ASP.NET, the FormView control rendered it contents using an item template. This made styling more difficult in the markup because unexpected table row and table cell tags were rendered by the control. The FormView control supports RenderOuterTable, a property in ASP.NET 4. When this property is set to false, as show in the following example, the table tags are not rendered. This makes it easier to apply CSS style to the contents of the control. <asp:FormView ID="FormView1" runat="server" RenderTable="false"> For more information, see FormView Web Server Control Overview. ListView Control Enhancements The ListView control, which was introduced in ASP.NET 3.5, has all the functionality of the GridView control while giving you complete control over the output. This control has been made easier to use in ASP.NET 4. The earlier version of the control required that you specify a layout template that contained a server control with a known ID. The following markup shows a typical example of how to use the ListView control in ASP.NET 3.5. <asp:ListView ID="ListView1" runat="server"> <LayoutTemplate> <asp:PlaceHolder ID="ItemPlaceHolder" runat="server"></asp:PlaceHolder> </LayoutTemplate> <ItemTemplate> <% Eval("LastName")%> </ItemTemplate> </asp:ListView> In ASP.NET 4, the ListView control does not require a layout template. The markup shown in the previous example can be replaced with the following markup: <asp:ListView ID="ListView1" runat="server"> <ItemTemplate> <% Eval("LastName")%> </ItemTemplate> </asp:ListView> For more information, see ListView Web Server Control Overview. Filtering Data with the QueryExtender Control A very common task for developers who create data-driven Web pages is to filter data. This traditionally has been performed by building Where clauses in data source controls. This approach can be complicated, and in some cases the Where syntax does not let you take advantage of the full functionality of the underlying database. To make filtering easier, a new QueryExtender control has been added in ASP.NET 4. This control can be added to EntityDataSource or LinqDataSource controls in order to filter the data returned by these controls. Because the QueryExtender control relies on LINQ, but you do not to need to know how to write LINQ queries to use the query extender. The QueryExtender control supports a variety of filter options. The following lists QueryExtender filter options. Term Definition SearchExpression Searches a field or fields for string values and compares them to a specified string value. RangeExpression Searches a field or fields for values in a range specified by a pair of values. PropertyExpression Compares a specified value to a property value in a field. If the expression evaluates to true, the data that is being examined is returned. OrderByExpression Sorts data by a specified column and sort direction. CustomExpression Calls a function that defines custom filter in the page. For more information, see QueryExtenderQueryExtender Web Server Control Overview. Enhanced Support for Web Standards and Accessibility Earlier versions of ASP.NET controls sometimes render markup that does not conform to HTML, XHTML, or accessibility standards. ASP.NET 4 eliminates most of these exceptions. For details about how the HTML that is rendered by each control meets accessibility standards, see ASP.NET Controls and Accessibility. CSS for Controls that Can be Disabled In ASP.NET 3.5, when a control is disabled (see WebControl.Enabled), a disabled attribute is added to the rendered HTML element. For example, the following markup creates a Label control that is disabled: <asp:Label id="Label1" runat="server" Text="Test" Enabled="false" /> In ASP.NET 3.5, the previous control settings generate the following HTML: <span id="Label1" disabled="disabled">Test</span> In HTML 4.01, the disabled attribute is not considered valid on span elements. It is valid only on input elements because it specifies that they cannot be accessed. On display-only elements such as span elements, browsers typically support rendering for a disabled appearance, but a Web page that relies on this non-standard behavior is not robust according to accessibility standards. For display-only elements, you should use CSS to indicate a disabled visual appearance. Therefore, by default ASP.NET 4 generates the following HTML for the control settings shown previously: <span id="Label1" class="aspNetDisabled">Test</span> You can change the value of the class attribute that is rendered by default when a control is disabled by setting the DisabledCssClass property. CSS for Validation Controls In ASP.NET 3.5, validation controls render a default color of red as an inline style. For example, the following markup creates a RequiredFieldValidator control: <asp:RequiredFieldValidator ID="RequiredFieldValidator1" runat="server" ErrorMessage="Required Field" ControlToValidate="RadioButtonList1" /> ASP.NET 3.5 renders the following HTML for the validator control: <span id="RequiredFieldValidator1" style="color:Red;visibility:hidden;">RequiredFieldValidator</span> By default, ASP.NET 4 does not render an inline style to set the color to red. An inline style is used only to hide or show the validator, as shown in the following example: <span id="RequiredFieldValidator1" style"visibility:hidden;">RequiredFieldValidator</span> Therefore, ASP.NET 4 does not automatically show error messages in red. For information about how to use CSS to specify a visual style for a validation control, see Validating User Input in ASP.NET Web Pages. CSS for the Hidden Fields Div Element ASP.NET uses hidden fields to store state information such as view state and control state. These hidden fields are contained by a div element. In ASP.NET 3.5, this div element does not have a class attribute or an id attribute. Therefore, CSS rules that affect all div elements could unintentionally cause this div to be visible. To avoid this problem, ASP.NET 4 renders the div element for hidden fields with a CSS class that you can use to differentiate the hidden fields div from others. The new classvalue is shown in the following example: <div class="aspNetHidden"> CSS for the Table, Image, and ImageButton Controls By default, in ASP.NET 3.5, some controls set the border attribute of rendered HTML to zero (0). The following example shows HTML that is generated by the Table control in ASP.NET 3.5: <table id="Table2" border="0"> The Image control and the ImageButton control also do this. Because this is not necessary and provides visual formatting information that should be provided by using CSS, the attribute is not generated in ASP.NET 4. CSS for the UpdatePanel and UpdateProgress Controls In ASP.NET 3.5, the UpdatePanel and UpdateProgress controls do not support expando attributes. This makes it impossible to set a CSS class on the HTMLelements that they render. In ASP.NET 4 these controls have been changed to accept expando attributes, as shown in the following example: <asp:UpdatePanel runat="server" class="myStyle"> </asp:UpdatePanel> The following HTML is rendered for this markup: <div id="ctl00_MainContent_UpdatePanel1" class="expandoclass"> </div> Eliminating Unnecessary Outer Tables In ASP.NET 3.5, the HTML that is rendered for the following controls is wrapped in a table element whose purpose is to apply inline styles to the entire control: FormView Login PasswordRecovery ChangePassword If you use templates to customize the appearance of these controls, you can specify CSS styles in the markup that you provide in the templates. In that case, no extra outer table is required. In ASP.NET 4, you can prevent the table from being rendered by setting the new RenderOuterTable property to false. Layout Templates for Wizard Controls In ASP.NET 3.5, the Wizard and CreateUserWizard controls generate an HTML table element that is used for visual formatting. In ASP.NET 4 you can use a LayoutTemplate element to specify the layout. If you do this, the HTML table element is not generated. In the template, you create placeholder controls to indicate where items should be dynamically inserted into the control. (This is similar to how the template model for the ListView control works.) For more information, see the Wizard.LayoutTemplate property. New HTML Formatting Options for the CheckBoxList and RadioButtonList Controls ASP.NET 3.5 uses HTML table elements to format the output for the CheckBoxList and RadioButtonList controls. To provide an alternative that does not use tables for visual formatting, ASP.NET 4 adds two new options to the RepeatLayout enumeration: UnorderedList. This option causes the HTML output to be formatted by using ul and li elements instead of a table. OrderedList. This option causes the HTML output to be formatted by using ol and li elements instead of a table. For examples of HTML that is rendered for the new options, see the RepeatLayout enumeration. Header and Footer Elements for the Table Control In ASP.NET 3.5, the Table control can be configured to render thead and tfoot elements by setting the TableSection property of the TableHeaderRow class and the TableFooterRow class. In ASP.NET 4 these properties are set to the appropriate values by default. CSS and ARIA Support for the Menu Control In ASP.NET 3.5, the Menu control uses HTML table elements for visual formatting, and in some configurations it is not keyboard-accessible. ASP.NET 4 addresses these problems and improves accessibility in the following ways: The generated HTML is structured as an unordered list (ul and li elements). CSS is used for visual formatting. The menu behaves in accordance with ARIA standards for keyboard access. You can use arrow keys to navigate menu items. (For information about ARIA, see Accessibility in Visual Studio and ASP.NET.) ARIA role and property attributes are added to the generated HTML. (Attributes are added by using JavaScript instead of included in the HTML, to avoid generating HTML that would cause markup validation errors.) Styles for the Menu control are rendered in a style block at the top of the page, instead of inline with the rendered HTML elements. If you want to use a separate CSS file so that you can modify the menu styles, you can set the Menu control's new IncludeStyleBlock property to false, in which case the style block is not generated. Valid XHTML for the HtmlForm Control In ASP.NET 3.5, the HtmlForm control (which is created implicitly by the <form runat="server"> tag) renders an HTML form element that has both name and id attributes. The name attribute is deprecated in XHTML 1.1. Therefore, this control does not render the name attribute in ASP.NET 4. Maintaining Backward Compatibility in Control Rendering An existing ASP.NET Web site might have code in it that assumes that controls are rendering HTML the way they do in ASP.NET 3.5. To avoid causing backward compatibility problems when you upgrade the site to ASP.NET 4, you can have ASP.NET continue to generate HTML the way it does in ASP.NET 3.5 after you upgrade the site. To do so, you can set the controlRenderingCompatibilityVersion attribute of the pages element to "3.5" in the Web.config file of an ASP.NET 4 Web site, as shown in the following example: <system.web> <pages controlRenderingCompatibilityVersion="3.5"/> </system.web> If this setting is omitted, the default value is the same as the version of ASP.NET that the Web site targets. (For information about multi-targeting in ASP.NET, see .NET Framework Multi-Targeting for ASP.NET Web Projects.) ASP.NET MVC ASP.NET MVC helps Web developers build compelling standards-based Web sites that are easy to maintain because it decreases the dependency among application layers by using the Model-View-Controller (MVC) pattern. MVC provides complete control over the page markup. It also improves testability by inherently supporting Test Driven Development (TDD). Web sites created using ASP.NET MVC have a modular architecture. This allows members of a team to work independently on the various modules and can be used to improve collaboration. For example, developers can work on the model and controller layers (data and logic), while the designer work on the view (presentation). For tutorials, walkthroughs, conceptual content, code samples, and a complete API reference, see ASP.NET MVC 2. Dynamic Data Dynamic Data was introduced in the .NET Framework 3.5 SP1 release in mid-2008. This feature provides many enhancements for creating data-driven applications, such as the following: A RAD experience for quickly building a data-driven Web site. Automatic validation that is based on constraints defined in the data model. The ability to easily change the markup that is generated for fields in the GridView and DetailsView controls by using field templates that are part of your Dynamic Data project. For ASP.NET 4, Dynamic Data has been enhanced to give developers even more power for quickly building data-driven Web sites. For more information, see ASP.NET Dynamic Data Content Map. Enabling Dynamic Data for Individual Data-Bound Controls in Existing Web Applications You can use Dynamic Data features in existing ASP.NET Web applications that do not use scaffolding by enabling Dynamic Data for individual data-bound controls. Dynamic Data provides the presentation and data layer support for rendering these controls. When you enable Dynamic Data for data-bound controls, you get the following benefits: Setting default values for data fields. Dynamic Data enables you to provide default values at run time for fields in a data control. Interacting with the database without creating and registering a data model. Automatically validating the data that is entered by the user without writing any code. For more information, see Walkthrough: Enabling Dynamic Data in ASP.NET Data-Bound Controls. New Field Templates for URLs and E-mail Addresses ASP.NET 4 introduces two new built-in field templates, EmailAddress.ascx and Url.ascx. These templates are used for fields that are marked as EmailAddress or Url using the DataTypeAttribute attribute. For EmailAddress objects, the field is displayed as a hyperlink that is created by using the mailto: protocol. When users click the link, it opens the user's e-mail client and creates a skeleton message. Objects typed as Url are displayed as ordinary hyperlinks. The following example shows how to mark fields. [DataType(DataType.EmailAddress)] public object HomeEmail { get; set; } [DataType(DataType.Url)] public object Website { get; set; } Creating Links with the DynamicHyperLink Control Dynamic Data uses the new routing feature that was added in the .NET Framework 3.5 SP1 to control the URLs that users see when they access the Web site. The new DynamicHyperLink control makes it easy to build links to pages in a Dynamic Data site. For information, see How to: Create Table Action Links in Dynamic Data Support for Inheritance in the Data Model Both the ADO.NET Entity Framework and LINQ to SQL support inheritance in their data models. An example of this might be a database that has an InsurancePolicy table. It might also contain CarPolicy and HousePolicy tables that have the same fields as InsurancePolicy and then add more fields. Dynamic Data has been modified to understand inherited objects in the data model and to support scaffolding for the inherited tables. For more information, see Walkthrough: Mapping Table-per-Hierarchy Inheritance in Dynamic Data. Support for Many-to-Many Relationships (Entity Framework Only) The Entity Framework has rich support for many-to-many relationships between tables, which is implemented by exposing the relationship as a collection on an Entity object. New field templates (ManyToMany.ascx and ManyToMany_Edit.ascx) have been added to provide support for displaying and editing data that is involved in many-to-many relationships. For more information, see Working with Many-to-Many Data Relationships in Dynamic Data. New Attributes to Control Display and Support Enumerations The DisplayAttribute has been added to give you additional control over how fields are displayed. The DisplayNameAttribute attribute in earlier versions of Dynamic Data enabled you to change the name that is used as a caption for a field. The new DisplayAttribute class lets you specify more options for displaying a field, such as the order in which a field is displayed and whether a field will be used as a filter. The attribute also provides independent control of the name that is used for the labels in a GridView control, the name that is used in a DetailsView control, the help text for the field, and the watermark used for the field (if the field accepts text input). The EnumDataTypeAttribute class has been added to let you map fields to enumerations. When you apply this attribute to a field, you specify an enumeration type. Dynamic Data uses the new Enumeration.ascx field template to create UI for displaying and editing enumeration values. The template maps the values from the database to the names in the enumeration. Enhanced Support for Filters Dynamic Data 1.0 had built-in filters for Boolean columns and foreign-key columns. The filters did not let you specify the order in which they were displayed. The new DisplayAttribute attribute addresses this by giving you control over whether a column appears as a filter and in what order it will be displayed. An additional enhancement is that filtering support has been rewritten to use the new QueryExtender feature of Web Forms. This lets you create filters without requiring knowledge of the data source control that the filters will be used with. Along with these extensions, filters have also been turned into template controls, which lets you add new ones. Finally, the DisplayAttribute class mentioned earlier allows the default filter to be overridden, in the same way that UIHint allows the default field template for a column to be overridden. For more information, see Walkthrough: Filtering Rows in Tables That Have a Parent-Child Relationship and QueryableFilterRepeater. ASP.NET Chart Control The ASP.NET chart server control enables you to create ASP.NET pages applications that have simple, intuitive charts for complex statistical or financial analysis. The chart control supports the following features: Data series, chart areas, axes, legends, labels, titles, and more. Data binding. Data manipulation, such as copying, splitting, merging, alignment, grouping, sorting, searching, and filtering. Statistical formulas and financial formulas. Advanced chart appearance, such as 3-D, anti-aliasing, lighting, and perspective. Events and customizations. Interactivity and Microsoft Ajax. Support for the Ajax Content Delivery Network (CDN), which provides an optimized way for you to add Microsoft Ajax Library and jQuery scripts to your Web applications. For more information, see Chart Web Server Control Overview. Visual Web Developer Enhancements The following sections provide information about enhancements and new features in Visual Studio 2010 and Visual Web Developer Express. The Web page designer in Visual Studio 2010 has been enhanced for better CSS compatibility, includes additional support for HTML and ASP.NET markup snippets, and features a redesigned version of IntelliSense for JScript. Improved CSS Compatibility The Visual Web Developer designer in Visual Studio 2010 has been updated to improve CSS 2.1 standards compliance. The designer better preserves HTML source code and is more robust than in previous versions of Visual Studio. HTML and JScript Snippets In the HTML editor, IntelliSense auto-completes tag names. The IntelliSense Snippets feature auto-completes whole tags and more. In Visual Studio 2010, IntelliSense snippets are supported for JScript, alongside C# and Visual Basic, which were supported in earlier versions of Visual Studio. Visual Studio 2010 includes over 200 snippets that help you auto-complete common ASP.NET and HTML tags, including required attributes (such as runat="server") and common attributes specific to a tag (such as ID, DataSourceID, ControlToValidate, and Text). You can download additional snippets, or you can write your own snippets that encapsulate the blocks of markup that you or your team use for common tasks. For more information on HTML snippets, see Walkthrough: Using HTML Snippets. JScript IntelliSense Enhancements In Visual 2010, JScript IntelliSense has been redesigned to provide an even richer editing experience. IntelliSense now recognizes objects that have been dynamically generated by methods such as registerNamespace and by similar techniques used by other JavaScript frameworks. Performance has been improved to analyze large libraries of script and to display IntelliSense with little or no processing delay. Compatibility has been significantly increased to support almost all third-party libraries and to support diverse coding styles. Documentation comments are now parsed as you type and are immediately leveraged by IntelliSense. Web Application Deployment with Visual Studio 2010 For Web application projects, Visual Studio now provides tools that work with the IIS Web Deployment Tool (Web Deploy) to automate many processes that had to be done manually in earlier versions of ASP.NET. For example, the following tasks can now be automated: Creating an IIS application on the destination computer and configuring IIS settings. Copying files to the destination computer. Changing Web.config settings that must be different in the destination environment. Propagating changes to data or data structures in SQL Server databases that are used by the Web application. For more information about Web application deployment, see ASP.NET Deployment Content Map. Enhancements to ASP.NET Multi-Targeting ASP.NET 4 adds new features to the multi-targeting feature to make it easier to work with projects that target earlier versions of the .NET Framework. Multi-targeting was introduced in ASP.NET 3.5 to enable you to use the latest version of Visual Studio without having to upgrade existing Web sites or Web services to the latest version of the .NET Framework. In Visual Studio 2008, when you work with a project targeted for an earlier version of the .NET Framework, most features of the development environment adapt to the targeted version. However, IntelliSense displays language features that are available in the current version, and property windows display properties available in the current version. In Visual Studio 2010, only language features and properties available in the targeted version of the .NET Framework are shown. For more information about multi-targeting, see the following topics: .NET Framework Multi-Targeting for ASP.NET Web Projects ASP.NET Side-by-Side Execution Overview How to: Host Web Applications That Use Different Versions of the .NET Framework on the Same Server How to: Deploy Web Site Projects Targeted for Earlier Versions of the .NET Framework

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FreeBSD performance tuning. Sysctls, loader.conf, kernel

- by SaveTheRbtz

I wanted to share knowledge of tuning FreeBSD via sysctl.conf/loader.conf/KENCONF. It was initially based on Igor Sysoev's (author of nginx) presentation about FreeBSD tuning up to 100,000-200,000 active connections. Tunings are for FreeBSD-CURRENT. Since 7.2 amd64 some of them are tuned well by default. Prior 7.0 some of them are boot only (set via /boot/loader.conf) or does not exist at all. sysctl.conf: # No zero mapping feature # May break wine # (There are also reports about broken samba3) #security.bsd.map_at_zero=0 # If you have really busy webserver with apache13 you may run out of processes #kern.maxproc=10000 # Same for servers with apache2 / Pound #kern.threads.max_threads_per_proc=4096 # Max. backlog size kern.ipc.somaxconn=4096 # Shared memory // 7.2+ can use shared memory > 2Gb kern.ipc.shmmax=2147483648 # Sockets kern.ipc.maxsockets=204800 # Can cause this on older kernels: # http://old.nabble.com/Significant-performance-regression-for-increased-maxsockbuf-on-8.0-RELEASE-tt26745981.html#a26745981 ) kern.ipc.maxsockbuf=10485760 # Mbuf 2k clusters (on amd64 7.2+ 25600 is default) # For such high value vm.kmem_size must be increased to 3G kern.ipc.nmbclusters=262144 # Jumbo pagesize(_SC_PAGESIZE) clusters # Used as general packet storage for jumbo frames # can be monitored via `netstat -m` #kern.ipc.nmbjumbop=262144 # Jumbo 9k/16k clusters # If you are using them #kern.ipc.nmbjumbo9=65536 #kern.ipc.nmbjumbo16=32768 # For lower latency you can decrease scheduler's maximum time slice # default: stathz/10 (~ 13) #kern.sched.slice=1 # Increase max command-line length showed in `ps` (e.g for Tomcat/Java) # Default is PAGE_SIZE / 16 or 256 on x86 # This avoids commands to be presented as [executable] in `ps` # For more info see: http://www.freebsd.org/cgi/query-pr.cgi?pr=120749 kern.ps_arg_cache_limit=4096 # Every socket is a file, so increase them kern.maxfiles=204800 kern.maxfilesperproc=200000 kern.maxvnodes=200000 # On some systems HPET is almost 2 times faster than default ACPI-fast # Useful on systems with lots of clock_gettime / gettimeofday calls # See http://old.nabble.com/ACPI-fast-default-timecounter,-but-HPET-83--faster-td23248172.html # After revision 222222 HPET became default: http://svnweb.freebsd.org/base?view=revision&revision=222222 kern.timecounter.hardware=HPET # Small receive space, only usable on http-server, on file server this # should be increased to 65535 or even more #net.inet.tcp.recvspace=8192 # This is useful on Fat-Long-Pipes #net.inet.tcp.recvbuf_max=10485760 #net.inet.tcp.recvbuf_inc=65535 # Small send space is useful for http servers that serve small files # Autotuned since 7.x net.inet.tcp.sendspace=16384 # This is useful on Fat-Long-Pipes #net.inet.tcp.sendbuf_max=10485760 #net.inet.tcp.sendbuf_inc=65535 # Turn off receive autotuning # You can play with it. #net.inet.tcp.recvbuf_auto=0 #net.inet.tcp.sendbuf_auto=0 # This should be enabled if you going to use big spaces (>64k) # Also timestamp field is useful when using syncookies net.inet.tcp.rfc1323=1 # Turn this off on high-speed, lossless connections (LAN 1Gbit+) # If you set it there is no need in TCP_NODELAY sockopt (see man tcp) net.inet.tcp.delayed_ack=0 # This feature is useful if you are serving data over modems, Gigabit Ethernet, # or even high speed WAN links (or any other link with a high bandwidth delay product), # especially if you are also using window scaling or have configured a large send window. # Automatically disables on small RTT ( http://www.freebsd.org/cgi/cvsweb.cgi/src/sys/netinet/tcp_subr.c?#rev1.237 ) # This sysctl was removed in 10-CURRENT: # See: http://www.mail-archive.com/[email protected]/msg06178.html #net.inet.tcp.inflight.enable=0 # TCP slowstart algorithm tunings # We assuming we have very fast clients #net.inet.tcp.slowstart_flightsize=100 #net.inet.tcp.local_slowstart_flightsize=100 # Disable randomizing of ports to avoid false RST # Before usage check SA here www.bsdcan.org/2006/papers/ImprovingTCPIP.pdf # (it's also says that port randomization auto-disables at some conn.rates, but I didn't checked it thou) #net.inet.ip.portrange.randomized=0 # Increase portrange # For outgoing connections only. Good for seed-boxes and ftp servers. net.inet.ip.portrange.first=1024 net.inet.ip.portrange.last=65535 # # stops route cache degregation during a high-bandwidth flood # http://www.freebsd.org/doc/en/books/handbook/securing-freebsd.html #net.inet.ip.rtexpire=2 net.inet.ip.rtminexpire=2 net.inet.ip.rtmaxcache=1024 # Security net.inet.ip.redirect=0 net.inet.ip.sourceroute=0 net.inet.ip.accept_sourceroute=0 net.inet.icmp.maskrepl=0 net.inet.icmp.log_redirect=0 net.inet.icmp.drop_redirect=1 net.inet.tcp.drop_synfin=1 # # There is also good example of sysctl.conf with comments: # http://www.thern.org/projects/sysctl.conf # # icmp may NOT rst, helpful for those pesky spoofed # icmp/udp floods that end up taking up your outgoing # bandwidth/ifqueue due to all that outgoing RST traffic. # #net.inet.tcp.icmp_may_rst=0 # Security net.inet.udp.blackhole=1 net.inet.tcp.blackhole=2 # IPv6 Security # For more info see http://www.fosslc.org/drupal/content/security-implications-ipv6 # Disable Node info replies # To see this vulnerability in action run `ping6 -a sglAac ::1` or `ping6 -w ::1` on unprotected node net.inet6.icmp6.nodeinfo=0 # Turn on IPv6 privacy extensions # For more info see proposal http://unix.derkeiler.com/Mailing-Lists/FreeBSD/net/2008-06/msg00103.html net.inet6.ip6.use_tempaddr=1 net.inet6.ip6.prefer_tempaddr=1 # Disable ICMP redirect net.inet6.icmp6.rediraccept=0 # Disable acceptation of RA and auto linklocal generation if you don't use them #net.inet6.ip6.accept_rtadv=0 #net.inet6.ip6.auto_linklocal=0 # Increases default TTL, sometimes useful # Default is 64 net.inet.ip.ttl=128 # Lessen max segment life to conserve resources # ACK waiting time in miliseconds # (default: 30000. RFC from 1979 recommends 120000) net.inet.tcp.msl=5000 # Max bumber of timewait sockets net.inet.tcp.maxtcptw=200000 # Don't use tw on local connections # As of 15 Apr 2009. Igor Sysoev says that nolocaltimewait has some buggy realization. # So disable it or now till get fixed #net.inet.tcp.nolocaltimewait=1 # FIN_WAIT_2 state fast recycle net.inet.tcp.fast_finwait2_recycle=1 # Time before tcp keepalive probe is sent # default is 2 hours (7200000) #net.inet.tcp.keepidle=60000 # Should be increased until net.inet.ip.intr_queue_drops is zero net.inet.ip.intr_queue_maxlen=4096 # Interrupt handling via multiple CPU, but with context switch. # You can play with it. Default is 1; #net.isr.direct=0 # This is for routers only #net.inet.ip.forwarding=1 #net.inet.ip.fastforwarding=1 # This speed ups dummynet when channel isn't saturated net.inet.ip.dummynet.io_fast=1 # Increase dummynet(4) hash #net.inet.ip.dummynet.hash_size=2048 #net.inet.ip.dummynet.max_chain_len # Should be increased when you have A LOT of files on server # (Increase until vfs.ufs.dirhash_mem becomes lower) vfs.ufs.dirhash_maxmem=67108864 # Note from commit http://svn.freebsd.org/base/head@211031 : # For systems with RAID volumes and/or virtualization envirnments, where # read performance is very important, increasing this sysctl tunable to 32 # or even more will demonstratively yield additional performance benefits. vfs.read_max=32 # Explicit Congestion Notification (see http://en.wikipedia.org/wiki/Explicit_Congestion_Notification) net.inet.tcp.ecn.enable=1 # Flowtable - flow caching mechanism # Useful for routers #net.inet.flowtable.enable=1 #net.inet.flowtable.nmbflows=65535 # Extreme polling tuning #kern.polling.burst_max=1000 #kern.polling.each_burst=1000 #kern.polling.reg_frac=100 #kern.polling.user_frac=1 #kern.polling.idle_poll=0 # IPFW dynamic rules and timeouts tuning # Increase dyn_buckets till net.inet.ip.fw.curr_dyn_buckets is lower net.inet.ip.fw.dyn_buckets=65536 net.inet.ip.fw.dyn_max=65536 net.inet.ip.fw.dyn_ack_lifetime=120 net.inet.ip.fw.dyn_syn_lifetime=10 net.inet.ip.fw.dyn_fin_lifetime=2 net.inet.ip.fw.dyn_short_lifetime=10 # Make packets pass firewall only once when using dummynet # i.e. packets going thru pipe are passing out from firewall with accept #net.inet.ip.fw.one_pass=1 # shm_use_phys Wires all shared pages, making them unswappable # Use this to lessen Virtual Memory Manager's work when using Shared Mem. # Useful for databases #kern.ipc.shm_use_phys=1 # ZFS # Enable prefetch. Useful for sequential load type i.e fileserver. # FreeBSD sets vfs.zfs.prefetch_disable to 1 on any i386 systems and # on any amd64 systems with less than 4GB of avaiable memory # For additional info check this nabble thread http://old.nabble.com/Samba-read-speed-performance-tuning-td27964534.html #vfs.zfs.prefetch_disable=0 # On highload servers you may notice following message in dmesg: # "Approaching the limit on PV entries, consider increasing either the # vm.pmap.shpgperproc or the vm.pmap.pv_entry_max tunable" vm.pmap.shpgperproc=2048 loader.conf: # Accept filters for data, http and DNS requests # Useful when your software uses select() instead of kevent/kqueue or when you under DDoS # DNS accf available on 8.0+ accf_data_load="YES" accf_http_load="YES" accf_dns_load="YES" # Async IO system calls aio_load="YES" # Linux specific devices in /dev # As for 8.1 it only /dev/full #lindev_load="YES" # Adds NCQ support in FreeBSD # WARNING! all ad[0-9]+ devices will be renamed to ada[0-9]+ # 8.0+ only #ahci_load="YES" #siis_load="YES" # FreeBSD 8.2+ # New Congestion Control for FreeBSD # http://caia.swin.edu.au/urp/newtcp/tools/cc_chd-readme-0.1.txt # http://www.ietf.org/proceedings/78/slides/iccrg-5.pdf # Initial merge commit message http://www.mail-archive.com/[email protected]/msg31410.html #cc_chd_load="YES" # Increase kernel memory size to 3G. # # Use ONLY if you have KVA_PAGES in kernel configuration, and you have more than 3G RAM # Otherwise panic will happen on next reboot! # # It's required for high buffer sizes: kern.ipc.nmbjumbop, kern.ipc.nmbclusters, etc # Useful on highload stateful firewalls, proxies or ZFS fileservers # (FreeBSD 7.2+ amd64 users: Check that current value is lower!) #vm.kmem_size="3G" # If your server has lots of swap (>4Gb) you should increase following value # according to http://lists.freebsd.org/pipermail/freebsd-hackers/2009-October/029616.html # Otherwise you'll be getting errors # "kernel: swap zone exhausted, increase kern.maxswzone" # kern.maxswzone="256M" # Older versions of FreeBSD can't tune maxfiles on the fly #kern.maxfiles="200000" # Useful for databases # Sets maximum data size to 1G # (FreeBSD 7.2+ amd64 users: Check that current value is lower!) #kern.maxdsiz="1G" # Maximum buffer size(vfs.maxbufspace) # You can check current one via vfs.bufspace # Should be lowered/upped depending on server's load-type # Usually decreased to preserve kmem # (default is 10% of mem) #kern.maxbcache="512M" # Sendfile buffers # For i386 only #kern.ipc.nsfbufs=10240 # FreeBSD 9+ # HPET "legacy route" support. It should allow HPET to work per-CPU # See http://www.mail-archive.com/[email protected]/msg03603.html #hint.atrtc.0.clock=0 #hint.attimer.0.clock=0 #hint.hpet.0.legacy_route=1 # syncache Hash table tuning net.inet.tcp.syncache.hashsize=1024 net.inet.tcp.syncache.bucketlimit=512 net.inet.tcp.syncache.cachelimit=65536 # Increased hostcache # Later host cache can be viewed via net.inet.tcp.hostcache.list hidden sysctl # Very useful for it's RTT RTTVAR # Must be power of two net.inet.tcp.hostcache.hashsize=65536 # hashsize * bucketlimit (which is 30 by default) # It allocates 255Mb (1966080*136) of RAM net.inet.tcp.hostcache.cachelimit=1966080 # TCP control-block Hash table tuning net.inet.tcp.tcbhashsize=4096 # Disable ipfw deny all # Should be uncommented when there is a chance that # kernel and ipfw binary may be out-of sync on next reboot #net.inet.ip.fw.default_to_accept=1 # # SIFTR (Statistical Information For TCP Research) is a kernel module that # logs a range of statistics on active TCP connections to a log file. # See prerelease notes http://groups.google.com/group/mailing.freebsd.current/browse_thread/thread/b4c18be6cdce76e4 # and man 4 sitfr #siftr_load="YES" # Enable superpages, for 7.2+ only # Also read http://lists.freebsd.org/pipermail/freebsd-hackers/2009-November/030094.html vm.pmap.pg_ps_enabled=1 # Usefull if you are using Intel-Gigabit NIC #hw.em.rxd=4096 #hw.em.txd=4096 #hw.em.rx_process_limit="-1" # Also if you have ALOT interrupts on NIC - play with following parameters # NOTE: You should set them for every NIC #dev.em.0.rx_int_delay: 250 #dev.em.0.tx_int_delay: 250 #dev.em.0.rx_abs_int_delay: 250 #dev.em.0.tx_abs_int_delay: 250 # There is also multithreaded version of em/igb drivers can be found here: # http://people.yandex-team.ru/~wawa/ # # for additional em monitoring and statistics use # sysctl dev.em.0.stats=1 ; dmesg # sysctl dev.em.0.debug=1 ; dmesg # Also after r209242 (-CURRENT) there is a separate sysctl for each stat variable; # Same tunings for igb #hw.igb.rxd=4096 #hw.igb.txd=4096 #hw.igb.rx_process_limit=100 # Some useful netisr tunables. See sysctl net.isr #net.isr.maxthreads=4 #net.isr.defaultqlimit=4096 #net.isr.maxqlimit: 10240 # Bind netisr threads to CPUs #net.isr.bindthreads=1 # # FreeBSD 9.x+ # Increase interface send queue length # See commit message http://svn.freebsd.org/viewvc/base?view=revision&revision=207554 #net.link.ifqmaxlen=1024 # Nicer boot logo =) loader_logo="beastie" And finally here is KERNCONF: # Just some of them, see also # cat /sys/{i386,amd64,}/conf/NOTES # This one useful only on i386 #options KVA_PAGES=512 # You can play with HZ in environments with high interrupt rate (default is 1000) # 100 is for my notebook to prolong it's battery life #options HZ=100 # Polling is goot on network loads with high packet rates and low-end NICs # NB! Do not enable it if you want more than one netisr thread #options DEVICE_POLLING # Eliminate datacopy on socket read-write # To take advantage with zero copy sockets you should have an MTU >= 4k # This req. is only for receiving data. # Read more in man zero_copy_sockets # Also this epic thread on kernel trap: # http://kerneltrap.org/node/6506 # Here Linus says that "anybody that does it that way (FreeBSD) is totally incompetent" #options ZERO_COPY_SOCKETS # Support TCP sign. Used for IPSec options TCP_SIGNATURE # There was stackoverflow found in KAME IPSec stack: # See http://secunia.com/advisories/43995/ # For quick workaround you can use `ipfw add deny proto ipcomp` options IPSEC # This ones can be loaded as modules. They described in loader.conf section #options ACCEPT_FILTER_DATA #options ACCEPT_FILTER_HTTP # Adding ipfw, also can be loaded as modules options IPFIREWALL # On 8.1+ you can disable verbose to see blocked packets on ipfw0 interface. # Also there is no point in compiling verbose into the kernel, because # now there is net.inet.ip.fw.verbose tunable. #options IPFIREWALL_VERBOSE #options IPFIREWALL_VERBOSE_LIMIT=10 options IPFIREWALL_FORWARD # Adding kernel NAT options IPFIREWALL_NAT options LIBALIAS # Traffic shaping options DUMMYNET # Divert, i.e. for userspace NAT options IPDIVERT # This is for OpenBSD's pf firewall device pf device pflog # pf's QoS - ALTQ options ALTQ options ALTQ_CBQ # Class Bases Queuing (CBQ) options ALTQ_RED # Random Early Detection (RED) options ALTQ_RIO # RED In/Out options ALTQ_HFSC # Hierarchical Packet Scheduler (HFSC) options ALTQ_PRIQ # Priority Queuing (PRIQ) options ALTQ_NOPCC # Required for SMP build # Pretty console # Manual can be found here http://forums.freebsd.org/showthread.php?t=6134 #options VESA #options SC_PIXEL_MODE # Disable reboot on Ctrl Alt Del #options SC_DISABLE_REBOOT # Change normal|kernel messages color options SC_NORM_ATTR=(FG_GREEN|BG_BLACK) options SC_KERNEL_CONS_ATTR=(FG_YELLOW|BG_BLACK) # More scroll space options SC_HISTORY_SIZE=8192 # Adding hardware crypto device device crypto device cryptodev # Useful network interfaces device vlan device tap #Virtual Ethernet driver device gre #IP over IP tunneling device if_bridge #Bridge interface device pfsync #synchronization interface for PF device carp #Common Address Redundancy Protocol device enc #IPsec interface device lagg #Link aggregation interface device stf #IPv4-IPv6 port # Also for my notebook, but may be used with Opteron device amdtemp # Same for Intel processors device coretemp # man 4 cpuctl device cpuctl # CPU control pseudo-device # Support for ECMP. More than one route for destination # Works even with default route so one can use it as LB for two ISP # For now code is unstable and panics (panic: rtfree 2) on route deletions. #options RADIX_MPATH # Multicast routing #options MROUTING #options PIM # Debug & DTrace options KDB # Kernel debugger related code options KDB_TRACE # Print a stack trace for a panic options KDTRACE_FRAME # amd64-only(?) options KDTRACE_HOOKS # all architectures - enable general DTrace hooks #options DDB #options DDB_CTF # all architectures - kernel ELF linker loads CTF data # Adaptive spining in lockmgr (8.x+) # See http://www.mail-archive.com/[email protected]/msg10782.html options ADAPTIVE_LOCKMGRS # UTF-8 in console (8.x+) #options TEKEN_UTF8 # FreeBSD 8.1+ # Deadlock resolver thread # For additional information see http://www.mail-archive.com/[email protected]/msg18124.html # (FYI: "resolution" is panic so use with caution) #options DEADLKRES # Increase maximum size of Raw I/O and sendfile(2) readahead #options MAXPHYS=(1024*1024) #options MAXBSIZE=(1024*1024) # For scheduler debug enable following option. # Debug will be available via `kern.sched.stats` sysctl # For more information see http://svnweb.freebsd.org/base/head/sys/conf/NOTES?view=markup #options SCHED_STATS If you are tuning network for maximum performance you may wish to play with ifconfig options like: # You can list all capabilities via `ifconfig -m` ifconfig [-]rxcsum [-]txcsum [-]tso [-]lro mtu In case you've enabled DDB in kernel config, you should edit your /etc/ddb.conf and add something like this to enable automatic reboot (and textdump as bonus): script kdb.enter.panic=textdump set; capture on; show pcpu; bt; ps; alltrace; capture off; call doadump; reset script kdb.enter.default=textdump set; capture on; bt; ps; capture off; call doadump; reset And do not forget to add ddb_enable="YES" to /etc/rc.conf Since FreeBSD 9 you can select to enable/disable flowcontrol on your NIC: # See http://en.wikipedia.org/wiki/Ethernet_flow_control and # http://www.mail-archive.com/[email protected]/msg07927.html for additional info ifconfig bge0 media auto mediaopt flowcontrol PS. Also most of FreeBSD's limits can be monitored by # vmstat -z and # limits PPS. variety of network counters can be monitored via # netstat -s In FreeBSD-9 netstat's -Q option appeared, try following command to display netisr stats # netstat -Q PPPS. also see # man 7 tuning PPPPS. I wanted to thank FreeBSD community, especially author of nginx - Igor Sysoev, nginx-ru@ and FreeBSD-performance@ mailing lists for providing useful information about FreeBSD tuning. FreeBSD WIP * Whats cooking for FreeBSD 7? * Whats cooking for FreeBSD 8? * Whats cooking for FreeBSD 9? So here is the question: What tunings are you using on yours FreeBSD servers? You can also post your /etc/sysctl.conf, /boot/loader.conf, kernel options, etc with description of its' meaning (do not copy-paste from sysctl -d). Don't forget to specify server type (web, smb, gateway, etc) Let's share experience!

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