output formatting - Page 629

which control in vs08 aspx c# will be able to take html tags as input and display it formatted accor

- by user287745

i asked a few questions regarding this and got answers that indicate i will have to make an costum build editor using ,markdown, .... to achieve something like stackoverflow.com/questions/ask page. there is time limitation and the requirements are that much, i have to achieve 1) allow users to using html tags when giving input 2) save that complete input to sql db 3) display the data in db withing a contol which renders the formatting as the tags specify. i am aware label and literal controls support html tags, the problem is how to allow the user to input the textbox does not seem the support html tags? thank you Need help in implementing the affect of the WRITE A NEW POST On stackoverflow.com <%--The editor--% <asp:UpdatePanel ID="UpdatePanel7" runat="server"> <ContentTemplate> <asp:Label ID="Label4" runat="server" Text="Label"></asp:Label> <div id="textchanging" onkeyup="textoftextbox('TextBox3'); return false;"> <asp:TextBox ID="TextBox3" runat="server" CausesValidation="True" ></asp:TextBox> </div> <%-- OnTextChanged="textoftextbox('TextBox3'); return false;" gives too man literals error. --%> <asp:Button ID="Button6" runat="server" Text="Post The Comment, The New, Write on Wall" onclick="Button6_Click" /> <asp:Label ID="Label2" runat="server" Text="Label"></asp:Label> <asp:TextBox ID="TextBox4" runat="server" CausesValidation="True"></asp:TextBox> <asp:Literal ID="Literal2" runat="server" Text="this must change" here comes the div <div id="displayingarea" runat="server">This area will change</div> </ContentTemplate> </asp:UpdatePanel> <%--The editor ends--%> protected void Button6_Click(object sender, EventArgs e) { Label3.Text = displayingarea.InnerHtml; } As you see, I have implemented the effect of typing text in textbox which appears as a reflection in the div WITH FULLY FORMATTED TEXT ACCORDIG TO THE HTML TAGS USED The textbox does not allow html! Well the text box doesnot have too, script just extracts what is typed, within letting the server know. The html of the div tag also changes as typed in textbox. Now, There is a “post” button within an update plane a avoid full post back of page What I needis when the button is clicked on the value withing the div tag “innerhtml” is passed on to the label. Yes I know the chnages are only made on the client side, So when the button click event occurs the server is not aware of the new data within the div tag, Therefore the server assign the original html withing the div to the lab. Need help to overcome this, How is it that what we enter text in the textbox press the button with coding like label1.text=textbox1.text; and it works even in update panel, but the aabove code for extracting innerhtml typed at users end similar to yping in textbox does not work?

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Differing styles in Python program: what do you suggest?

- by Noctis Skytower

A friend of mine wanted help learning to program, so he gave me all the programs that he wrote for his previous classes. The last program that he wrote was an encryption program, and after rewriting all his programs in Python, this is how his encryption program turned out (after adding my own requirements). #! /usr/bin/env python ################################################################################ """\ CLASS INFORMATION ----------------- Program Name: Program 11 Programmer: Stephen Chappell Instructor: Stephen Chappell for CS 999-0, Python Due Date: 17 May 2010 DOCUMENTATION ------------- This is a simple encryption program that can encode and decode messages.""" ################################################################################ import sys KEY_FILE = 'Key.txt' BACKUP = '''\ !"#$%&'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNO\ PQRSTUVWXYZ[\]^_`abcdefghijklmnopqrstuvwxyz{|}~ _@/6-UC'GzaV0%5Mo9g+yNh8b">Bi=<Lx [sQn#^R.D2Xc(\ Jm!4e${lAEWud&t7]H\`}pvPw)FY,Z~?qK|3SOfk*:1;jTrI''' ################################################################################ def main(): "Run the program: loads key, runs processing loop, and saves key." encode_map, decode_map = load_key(KEY_FILE) try: run_interface_loop(encode_map, decode_map) except SystemExit: pass save_key(KEY_FILE, encode_map) def run_interface_loop(encode_map, decode_map): "Shows the menu and runs the appropriate command." print('This program handles encryption via a customizable key.') while True: print('''\ MENU ==== (1) Encode (2) Decode (3) Custom (4) Finish''') switch = get_character('Select: ', tuple('1234')) FUNC[switch](encode_map, decode_map) def get_character(prompt, choices): "Gets a valid menu option and returns it." while True: sys.stdout.write(prompt) sys.stdout.flush() line = sys.stdin.readline()[:-1] if not line: sys.exit() if line in choices: return line print(repr(line), 'is not a valid choice.') ################################################################################ def load_key(filename): "Gets the key file data and returns encoding/decoding dictionaries." plain, cypher = open_file(filename) return dict(zip(plain, cypher)), dict(zip(cypher, plain)) def open_file(filename): "Load the keys and tries to create it when not available." while True: try: with open(filename) as file: plain, cypher = file.read().split('\n') return plain, cypher except: with open(filename, 'w') as file: file.write(BACKUP) def save_key(filename, encode_map): "Dumps the map into two buffers and saves them to the key file." plain = cypher = str() for p, c in encode_map.items(): plain += p cypher += c with open(filename, 'w') as file: file.write(plain + '\n' + cypher) ################################################################################ def encode(encode_map, decode_map): "Encodes message for the user." print('Enter your message to encode (EOF when finished).') message = get_message() for char in message: sys.stdout.write(encode_map[char] if char in encode_map else char) def decode(encode_map, decode_map): "Decodes message for the user." print('Enter your message to decode (EOF when finished).') message = get_message() for char in message: sys.stdout.write(decode_map[char] if char in decode_map else char) def custom(encode_map, decode_map): "Allows user to edit the encoding/decoding dictionaries." plain, cypher = get_new_mapping() for p, c in zip(plain, cypher): encode_map[p] = c decode_map[c] = p ################################################################################ def get_message(): "Gets and returns text entered by the user (until EOF)." buffer = [] while True: line = sys.stdin.readline() if line: buffer.append(line) else: return ''.join(buffer) def get_new_mapping(): "Prompts for strings to edit encoding/decoding maps." while True: plain = get_unique_chars('What do you want to encode from?') cypher = get_unique_chars('What do you want to encode to?') if len(plain) == len(cypher): return plain, cypher print('Both lines should have the same length.') def get_unique_chars(prompt): "Gets strings that only contain unique characters." print(prompt) while True: line = input() if len(line) == len(set(line)): return line print('There were duplicate characters: please try again.') ################################################################################ # This map is used for dispatching commands in the interface loop. FUNC = {'1': encode, '2': decode, '3': custom, '4': lambda a, b: sys.exit()} ################################################################################ if __name__ == '__main__': main() For all those Python programmers out there, your help is being requested. How should the formatting (not necessarily the coding by altered to fit Python's style guide? My friend does not need to be learning things that are not correct. If you have suggestions on the code, feel free to post them to this wiki as well.

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can't the asp file system object access shares server paths?

- by sushant

i am using this code to access files and folders. <%@ Language=VBScript %><% option explicit dim sRoot, sDir, sParent, objFSO, objFolder, objFile, objSubFolder, sSize %> <META content="Microsoft Visual Studio 6.0" name=GENERATOR> <% sRoot = "D:Raghu" sDir = Request("Dir") sDir = sDir & "\" Response.Write "<h1>" & sDir & "</h1>" & vbCRLF Set objFSO = CreateObject("Scripting.FileSystemObject") on error resume next Set objFolder = objFSO.GetFolder(sRoot & sDir) if err.number <> 0 then Response.Write "Could not open folder" Response.End end if on error goto 0 sParent = objFSO.GetParentFolderName(objFolder.Path) ' Remove the contents of sRoot from the front. This gives us the parent ' path relative to the root folder ' eg. if parent folder is "c:webfilessubfolder1subfolder2" then we just want "subfolder1subfolder2" sParent = mid(sParent, len(sRoot) + 1) Response.Write "<table border=""1"">" ' Give a link to the parent folder. This is just a link to this page only pssing in ' the new folder as a parameter Response.Write "<tr><td colspan=3><a href=""browse.asp?dir=" & Server.URLEncode(sParent) & """>Parent folder</a></td></tr>" & vbCRLF ' Now we want to loop through the subfolders in this folder For Each objSubFolder In objFolder.SubFolders ' And provide a link to them Response.Write "<tr><td colspan=3><a href=""browse.asp?dir=" & Server.URLEncode(sDir & objSubFolder.Name) & """>" & objSubFolder.Name & "</a></td></tr>" & vbCRLF Next ' Now we want to loop through the files in this folder For Each objFile In objFolder.Files if Clng(objFile.Size) < 1024 then sSize = objFile.Size & " bytes" else sSize = Clng(objFile.Size / 1024) & " KB" end if ' And provide a link to view them. This is a link to show.asp passing in the directory and the file ' as parameters Response.Write "<tr><td><a href=""show.asp?file=" & server.URLEncode(objFile.Name) & "&dir=" & server.URLEncode (sDir) & """>" & objFile.Name & "</a></td><td>" & sSize & "</td><td>" & objFile.Type & "</td></tr>" & vbCRLF Next Response.Write "</table>" %> it works fine. but when i try to access something on shred path like: "\\cvrdd0110:share" it gives error. how to access these files? and sorry for formatting issues.

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How to Print in VS10, Printing gives unhandled exception. Access Denied

- by Smoka

Im newish to coding, currently on a Windows Forms App using CLI in VS10 Everything seems to work, my document shows fine in the Preview dialog but then crash's. Heres only the code that seems relevant private: System::Drawing::Printing::PrintDocument^ docPrint; private: System::Windows::Forms::PrintDialog^ dlgPrint; private: System::Windows::Forms::PrintPreviewDialog^ dlgPrintPreview; this->button2 = (gcnew System::Windows::Forms::Button()); this->docPrint = (gcnew System::Drawing::Printing::PrintDocument()); this->dlgPrint = (gcnew System::Windows::Forms::PrintDialog()); this->dlgPrintPreview = (gcnew System::Windows::Forms::PrintPreviewDialog()); this->button2->Location = System::Drawing::Point(152, 355); this->button2->Name = L"button2"; this->button2->Size = System::Drawing::Size(75, 23); this->button2->TabIndex = 53; this->button2->Text = L"Print"; this->button2->UseVisualStyleBackColor = true; this->button2->Click += gcnew System::EventHandler(this, &Form1::button2_Click_1); // // docPrint // this->docPrint->DocumentName = L"ResultsPage"; this->docPrint->PrintPage += gcnew System::Drawing::Printing::PrintPageEventHandler(this, &Form1::docPrint_PrintPage); // // dlgPrint // this->dlgPrint->Document = this->docPrint; this->dlgPrint->UseEXDialog = true; // // dlgPrintPreview // this->dlgPrintPreview->AutoScrollMargin = System::Drawing::Size(0, 0); this->dlgPrintPreview->AutoScrollMinSize = System::Drawing::Size(0, 0); this->dlgPrintPreview->ClientSize = System::Drawing::Size(400, 300); this->dlgPrintPreview->Document = this->docPrint; this->dlgPrintPreview->Enabled = true; this->dlgPrintPreview->Icon = (cli::safe_cast<System::Drawing::Icon^ >(resources->GetObject(L"dlgPrintPreview.Icon"))); this->dlgPrintPreview->Name = L"dlgPrintPreview"; this->dlgPrintPreview->Visible = false; this->dlgPrintPreview->Load += gcnew System::EventHandler(this, &Form1::dlgPrintPreview_Load); private: System::Void docPrint_PrintPage(System::Object^ sender, System::Drawing::Printing::PrintPageEventArgs^ e) { String ^ strDisplay = L"A Axis Rotations"; String ^ strDisplay2 = L"Centerline of Y" + CL_Y->Text + " + Z" + CL_Z->Text; String ^ strDisplay3 = L"Initial Position Y" + G54_Y->Text + " + Z" + G54_Z->Text; System::Drawing::Font ^ fntString = gcnew System::Drawing::Font(L"Times New Roman", 38, FontStyle::Bold); e->Graphics->DrawString(strDisplay, fntString, Brushes::Black, 200,20); e->Graphics->DrawString(strDisplay2, fntString, Brushes::Black, 80,150); e->Graphics->DrawString(strDisplay3, fntString, Brushes::Black, 80,220); e->Graphics->DrawString(Results->Text, fntString,Brushes::Black, 50,400); } private: System::Void button2_Click_1(System::Object^ sender, System::EventArgs^ e) { // docPrint->Print; dlgPrintPreview->ShowDialog(); } private: System::Void dlgPrintPreview_Load(System::Object^ sender, System::EventArgs^ e) { } Sorry if the formatting is ugly here. In case this is all wrong. what is the minimum requirements in code for a print job? Is there an easier way?

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Intrinsics program (SSE) - g++ - help needed

- by Sriram

Hi all, This is the first time I am posting a question on stackoverflow, so please try and overlook any errors I may have made in formatting my question/code. But please do point the same out to me so I may be more careful. I was trying to write some simple intrinsics routines for the addition of two 128-bit (containing 4 float variables) numbers. I found some code on the net and was trying to get it to run on my system. The code is as follows: //this is a sample Intrinsics program to add two vectors. #include <iostream> #include <iomanip> #include <xmmintrin.h> #include <stdio.h> using namespace std; struct vector4 { float x, y, z, w; }; //functions to operate on them. vector4 set_vector(float x, float y, float z, float w = 0) { vector4 temp; temp.x = x; temp.y = y; temp.z = z; temp.w = w; return temp; } void print_vector(const vector4& v) { cout << " This is the contents of vector: " << endl; cout << " > vector.x = " << v.x << endl; cout << " vector.y = " << v.y << endl; cout << " vector.z = " << v.z << endl; cout << " vector.w = " << v.w << endl; } vector4 sse_vector4_add(const vector4&a, const vector4& b) { vector4 result; asm volatile ( "movl $a, %eax" //move operands into registers. "\n\tmovl $b, %ebx" "\n\tmovups (%eax), xmm0" //move register contents into SSE registers. "\n\tmovups (%ebx), xmm1" "\n\taddps xmm0, xmm1" //add the elements. addps operates on single-precision vectors. "\n\t movups xmm0, result" //move result into vector4 type data. ); return result; } int main() { vector4 a, b, result; a = set_vector(1.1, 2.1, 3.2, 4.5); b = set_vector(2.2, 4.2, 5.6); result = sse_vector4_add(a, b); print_vector(a); print_vector(b); print_vector(result); return 0; } The g++ parameters I use are: g++ -Wall -pedantic -g -march=i386 -msse intrinsics_SSE_example.C -o h The errors I get are as follows: intrinsics_SSE_example.C: Assembler messages: intrinsics_SSE_example.C:45: Error: too many memory references for movups intrinsics_SSE_example.C:46: Error: too many memory references for movups intrinsics_SSE_example.C:47: Error: too many memory references for addps intrinsics_SSE_example.C:48: Error: too many memory references for movups I have spent a lot of time on trying to debug these errors, googled them and so on. I am a complete noob to Intrinsics and so may have overlooked some important things. Any help is appreciated, Thanks, Sriram.

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Javascript phsyics in a 2d space

- by eroo

So, I am working on teaching myself Canvas (HTML5) and have most of a simple game engine coded up. It is a 2d representation of a space scene (planets, stars, celestial bodies, etc). My default "Sprite" class has a frame listener like such: "baseClass" contains a function that allows inheritance and applies "a" to "this.a". So, "var aTest = new Sprite({foo: 'bar'});" would make "aTest.foo = 'bar'". This is how I expose my objects to each other. { Sprite = baseClass.extend({ init: function(a){ baseClass.init(this, a); this.fields = new Array(); // list of fields of gravity one is in. Not sure if this is a good idea. this.addFL(function(tick){ // this will change to be independent of framerate soon. // and this is where I need help // gobjs is an array of all the Sprite objects in the "world". for(i = 0; i < gobjs.length; i++){ // Make sure its got setup correctly, make sure it -wants- gravity, and make sure it's not -this- sprite. if(typeof(gobjs[i].a) != undefined && !gobjs[i].a.ignoreGravity && gobjs[i].id != this.id){ // Check if it's within a certain range (obviously, gravity doesn't work this way... But I plan on having a large "space" area, // And I can't very well have all objects accounted for at all times, can I? if(this.distanceTo(gobjs[i]) < this.s.size*10 && gobjs[i].fields.indexOf(this.id) == -1){ gobjs[i].fields.push(this.id); } } } for(i = 0; i < this.fields.length; i++){ distance = this.distanceTo(gobjs[this.fields[i]]); angletosun = this.angleTo(gobjs[this.fields[i]])*(180/Math.PI); // .angleTo works very well, returning the angle in radians, which I convert to degrees here. // I have no idea what should happen here, although through trial and error (and attempting to read Maths papers on gravity (eeeeek!)), this sort of mimics gravity. // angle is its orientation, currently I assign a constant velocity to one of my objects, and leave the other static (it ignores gravity, but still emits it). this.a.angle = angletosun+(75+(distance*-1)/5); //todo: omg learn math if(this.distanceTo(gobjs[this.fields[i]]) > gobjs[this.fields[i]].a.size*10) this.fields.splice(i); // out of range, stop effecting. } }); } }); } Thanks in advance. The real trick is that one line: { this.a.angle = angletosun+(75+(distance*-1)/5); } This is more a physics question than Javascript, but I've searched and searched and read way to many wiki articles on orbital mathematics. It gets over my head very quickly. Edit: There is a weirdness with the SO formatting; forgives me, I is noobie.

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Generating cache file for Twitter rss feed

- by Kerri

I'm working on a site with a simple php-generated twitter box with user timeline tweets pulled from the user_timeline rss feed, and cached to a local file to cut down on loads, and as backup for when twitter goes down. I based the caching on this: http://snipplr.com/view/8156/twitter-cache/. It all seemed to be working well yesterday, but today I discovered the cache file was blank. Deleting it then loading again generated a fresh file. The code I'm using is below. I've edited it to try to get it to work with what I was already using to display the feed and probably messed something crucial up. The changes I made are the following (and I strongly believe that any of these could be the cause): - Revised the time difference code (the linked example seemed to use a custom function that wasn't included in the code) Removed the "serialize" function from the "fwrites". This is purely because I couldn't figure out how to unserialize once I loaded it in the display code. I truthfully don't understand the role that serialize plays or how it works, so I'm sure I should have kept it in. If that's the case I just need to understand where/how to deserialize in the second part of the code so that it can be parsed. Removed the $rss variable in favor of just loading up the cache file in my original tweet display code. So, here are the relevant parts of the code I used: <?php $feedURL = "http://twitter.com/statuses/user_timeline/#######.rss"; // START CACHING $cache_file = dirname(__FILE__).'/cache/twitter_cache.rss'; // Start with the cache if(file_exists($cache_file)){ $mtime = (strtotime("now") - filemtime($cache_file)); if($mtime > 600) { $cache_rss = file_get_contents('http://twitter.com/statuses/user_timeline/75168146.rss'); $cache_static = fopen($cache_file, 'wb'); fwrite($cache_static, $cache_rss); fclose($cache_static); } echo ""; } else { $cache_rss = file_get_contents('http://twitter.com/statuses/user_timeline/#######.rss'); $cache_static = fopen($cache_file, 'wb'); fwrite($cache_static, $cache_rss); fclose($cache_static); } //END CACHING //START DISPLAY $doc = new DOMDocument(); $doc->load($cache_file); $arrFeeds = array(); foreach ($doc->getElementsByTagName('item') as $node) { $itemRSS = array ( 'title' => $node->getElementsByTagName('title')->item(0)->nodeValue, 'date' => $node->getElementsByTagName('pubDate')->item(0)->nodeValue ); array_push($arrFeeds, $itemRSS); } // the rest of the formatting and display code.... } ?> ETA 6/17 Nobody can help…? I'm thinking it has something to do with writing a blank cache file over a good one when twitter is down, because otherwise I imagine that this should be happening every ten minutes when the cache file is overwritten again, but it doesn't happen that frequently. I made the following change to the part where it checks how old the file is to overwrite it: $cache_rss = file_get_contents('http://twitter.com/statuses/user_timeline/75168146.rss'); if($mtime > 600 && $cache_rss != ''){ $cache_static = fopen($cache_file, 'wb'); fwrite($cache_static, $cache_rss); fclose($cache_static); } …so now, it will only write the file if it's over ten minutes old and there's actual content retrieved from the rss page. Do you think this will work?

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can't the asp file system object access shared server paths?

- by sushant

i am using this code to access files and folders. <%@ Language=VBScript %><% option explicit dim sRoot, sDir, sParent, objFSO, objFolder, objFile, objSubFolder, sSize %> <META content="Microsoft Visual Studio 6.0" name=GENERATOR> <% sRoot = "D:Raghu" sDir = Request("Dir") sDir = sDir & "\" Response.Write "<h1>" & sDir & "</h1>" & vbCRLF Set objFSO = CreateObject("Scripting.FileSystemObject") on error resume next Set objFolder = objFSO.GetFolder(sRoot & sDir) if err.number <> 0 then Response.Write "Could not open folder" Response.End end if on error goto 0 sParent = objFSO.GetParentFolderName(objFolder.Path) ' Remove the contents of sRoot from the front. This gives us the parent ' path relative to the root folder ' eg. if parent folder is "c:webfilessubfolder1subfolder2" then we just want "subfolder1subfolder2" sParent = mid(sParent, len(sRoot) + 1) Response.Write "<table border=""1"">" ' Give a link to the parent folder. This is just a link to this page only pssing in ' the new folder as a parameter Response.Write "<tr><td colspan=3><a href=""browse.asp?dir=" & Server.URLEncode(sParent) & """>Parent folder</a></td></tr>" & vbCRLF ' Now we want to loop through the subfolders in this folder For Each objSubFolder In objFolder.SubFolders ' And provide a link to them Response.Write "<tr><td colspan=3><a href=""browse.asp?dir=" & Server.URLEncode(sDir & objSubFolder.Name) & """>" & objSubFolder.Name & "</a></td></tr>" & vbCRLF Next ' Now we want to loop through the files in this folder For Each objFile In objFolder.Files if Clng(objFile.Size) < 1024 then sSize = objFile.Size & " bytes" else sSize = Clng(objFile.Size / 1024) & " KB" end if ' And provide a link to view them. This is a link to show.asp passing in the directory and the file ' as parameters Response.Write "<tr><td><a href=""show.asp?file=" & server.URLEncode(objFile.Name) & "&dir=" & server.URLEncode (sDir) & """>" & objFile.Name & "</a></td><td>" & sSize & "</td><td>" & objFile.Type & "</td></tr>" & vbCRLF Next Response.Write "</table>" %> it works fine. but when i try to access something on shared path like: "\\cvrdd0110:share" it gives error. how to access these files? and sorry for formatting issues.

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Displaying unnecessary HTML when showing content from MySQL database.

- by ThatMacLad

My homepage pulls in content from my MySQL database to create a blog. I've got it so that it only displays an extract from the posts. For some reason it displays HTML tags as well rather than formatting it using the tags (See picture below). Any help is appreciated. Homepage: <html> <head> <title>Ultan Casey | Homepage</title> <link rel="stylesheet" href="css/style.css" type="text/css" /> </head> <body> <div class="wrapper"> <div id="upperbar"> <a href="#">Home</a> <a href="#">About Me</a> <a href="#">Contact Me</a> <a href="http://www.twitter.com/UltanKC">Twitter</a> <form id="search-form" action="/search" method="get"> <input type="text" id="textarea" size="33" name="q" value=""/> <input type="submit" id="submit" value="Search"/> </form> </div> <div id="banner"> <img src="images/banner.jpg"> </div> <div class="sidebar"></div> <div class="posts"> <?php mysql_connect ('localhost', 'root', 'root') ; mysql_select_db ('tmlblog'); $sql = "SELECT * FROM php_blog ORDER BY timestamp DESC LIMIT 5"; $result = mysql_query($sql) or print ("Can't select entries from table php_blog.<br />" . $sql . "<br />" . mysql_error()); while($row = mysql_fetch_array($result)) { $date = date("l F d Y", $row['timestamp']); $title = stripslashes($row['title']); $entry = stripslashes($row['entry']); $id = $row['id']; ?> <?php echo "<p id='title'><strong><a href=\"post.php?id=". $id . "\">" . $title . "</a></strong></p>"; ?><br /> <div class="post-thumb"><img src="thumbs/<?php echo $id ?>.png"></div> <?php echo htmlspecialchars(substr($entry, 0, 1050)) ?>... <br> <hr><br /> Posted on <?php echo $date; ?> </p> </div> </div> </p <?php } ?> </div> </div> </div> </body> </html> Image:

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populate uipicker view with results from core data DB using an NSArray

- by Chris

I am trying to populate a UIPickerView with the results of a NSFetchRequest. The results of the NSFetchRequest are then stored in an NSArray. I am using Core Data to interact with the SQLite DB. I have a simple class file that contains a UIPickerView that is associated with a storyboard scene in my project. The header file for the class looks like the following, ViewControllerUsers.h #import <UIKit/UIKit.h> #import "AppDelegate.h" @interface ViewControllerUsers : UIViewController <NSFetchedResultsControllerDelegate, UIPickerViewDelegate, UIPickerViewDataSource> { NSArray *dictionaries; } @property (nonatomic, strong) NSFetchedResultsController *fetchedResultsController; // Core Data @property (strong, nonatomic) NSManagedObjectContext *managedObjectContext; @property (nonatomic, strong) NSArray *users; @property (strong, nonatomic) IBOutlet UIPickerView *uiPickerViewUsers; @property (weak, nonatomic) IBOutlet UIBarButtonItem *btnDone; @property (weak, nonatomic) IBOutlet UIButton *btnChangePin; // added for testing purposes @property (nonatomic, strong) NSArray *usernames; - (IBAction)dismissScene:(id)sender; - (IBAction)changePin:(id)sender; @end The implementation file looks like the following, ViewControllerUsers.m #import "ViewControllerUsers.h" @interface ViewControllerUsers () @end @implementation ViewControllerUsers // Core Data @synthesize managedObjectContext = _managedObjectContext; @synthesize uiPickerViewUsers = _uiPickerViewUsers; @synthesize usernames = _usernames; - (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil { self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil]; if (self) { // Custom initialization } return self; } - (void)viewDidLoad { [super viewDidLoad]; // Do any additional setup after loading the view. // Core Data if (_managedObjectContext == nil) { _managedObjectContext = [(AppDelegate *)[[UIApplication sharedApplication] delegate] managedObjectContext]; NSLog(@"After _managedObjectContext: %@", _managedObjectContext); } NSFetchRequest *request = [NSFetchRequest fetchRequestWithEntityName:@"Account"]; NSEntityDescription *entity = [NSEntityDescription entityForName:@"Account" inManagedObjectContext:_managedObjectContext]; request.resultType = NSDictionaryResultType; request.propertiesToFetch = [NSArray arrayWithObject:[[entity propertiesByName] objectForKey:@"username"]]; request.returnsDistinctResults = YES; _usernames = [_managedObjectContext executeFetchRequest:request error:nil]; NSLog (@"names: %@",_usernames); } -(NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView { //One column return 1; } -(NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent:(NSInteger)component { //set number of rows return _usernames.count; } -(NSString *)pickerView:(UIPickerView *)pickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component { //set item per row return [_usernames objectAtIndex:row]; } - (void)didReceiveMemoryWarning { [super didReceiveMemoryWarning]; // Dispose of any resources that can be recreated. } - (void)viewDidUnload { [self setBtnDone:nil]; [self setUiPickerViewUsers:nil]; [self setBtnChangePin:nil]; [super viewDidUnload]; } - (IBAction)dismissScene:(id)sender { [self dismissModalViewControllerAnimated:YES]; } - (IBAction)changePin:(id)sender { } @end The current code is causing the app to crash, but the NSLog is show the results of the NSFetchRequest in the NSArray. I currently think that I am not formatting the results of the NSFetchRequest in the NSArray properly if I had to take a guess. The crash log looks like the following, 2013-06-26 16:49:24.219 KegCop[41233:c07] names: ( { username = blah; }, { username = chris; }, { username = root; } ) 2013-06-26 16:49:24.223 KegCop[41233:c07] -[NSKnownKeysDictionary1 isEqualToString:]: unrecognized selector sent to instance 0xe54d9a0 2013-06-26 16:49:24.223 KegCop[41233:c07] Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[NSKnownKeysDictionary1 isEqualToString:]: unrecognized selector sent to instance 0xe54d9a0' First throw call stack:

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Having trouble storing a CRTP based class in a vector

- by user366834

Hi, Im not sure if this can be done, im just delving into templates so perhaps my understanding is a bit wrong. I have a Platoon of soldiers, the platoon inherits from a formation to pick up the formations properties, but because i could have as many formations as i can think of I chose to use the CRTP to create the formations, hoping that i could make a vector or array of Platoon to store the platoons in. but, of course, when i make a Platoon, it wont store it in the vector, "types are unrelated" Is there any way around this ? i read about "Veneers" which are similar and that they work with arrays but i cant get it to work, perhaps im missing something. here's some code: (sorry about the formatting, the code is here in my post but its not showing up for some reason ) template < class TBase > class IFormation { public : ~IFormation(){} bool IsFull() { return m_uiMaxMembers == m_uiCurrentMemCount; } protected: unsigned int m_uiCurrentMemCount; unsigned int m_uiMaxMembers; IFormation( unsigned int _uiMaxMembers ): m_uiMaxMembers( _uiMaxMembers ), m_uiCurrentMemCount( 0 ){} // only allow use as a base class. void SetupFormation( std::vector<MySoldier*>& _soldierList ){}; // must be implemented in derived class }; ///////////////////////////////////////////////////////////////////////////////// // PHALANX FORMATION class Phalanx : public IFormation<Phalanx> { public: Phalanx( ): IFormation( 12 ), m_fDistance( 4.0f ) {} ~Phalanx(){} protected: float m_fDistance; // the distance between soldiers void SetupFormation( std::vector<MySoldier*>& _soldierList ); }; /////////////////////////////////////////////////////////////////////////////////// // COLUMN FORMATINO class Column : public IFormation< Column > { public : Column( int _numOfMembers ): IFormation( _numOfMembers ) {} ~Column(); protected: void SetupFormation( std::vector<MySoldier*>& _soldierList ); }; I then use these formations in the platoon class to derive, so that platoon gets the relevant SetupFormation() function: template < class Formation > class Platoon : public Formation { public: **** platoon code here }; everything works great and as expected up until this point. now, as my general can have multiple platoons, I need to store the platoons. typedef Platoon< IFormation<> > TPlatoon; // FAIL typedef std::vector<TPlatoon*> TPlatoons; TPlatoon m_pPlatoons m_pPlatoons.push_back( new Platoon<Phalanx> ); // FAIL, types unrelated. typedef Platoon< IFormation< TPlatoon; fails because i need to specify a template parameter, yet specifying this will only allow me to store platoons created with the same template parameter. so i then created FormationBase class FormationBase { public: virtual bool IsFull() = 0; virtual void SetupFormation( std::vector<MySoldier*>& _soldierList ) = 0; }; and made IFormation publicly inherit from that, and then changed the typedef to typedef Platoon< IFormation< FormationBase > > TPlatoon; but still no love. now in my searches i have not found info that says this is possible - or not possible.

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Use JQuery to target unwrapped text inside a div

- by Chris

I'm trying to find a way to wrap just the inner text of an element, I don't want to target any other inner dom elements. For example. <ul> <li class="this-one"> this is my item <ul> <li> this is a sub element </li> </ul> </li> </ul> I want to use jQuery to do this. <ul> <li class="this-one"> <div class="tree-item-text">this is my item</div> <ul> <li> <div class="tree-item-text">this is a sub element</div> </li> </ul> </li> </ul> A little background is I need to make an in-house tree structure ui element, So I'm using the UL structure to represent this. But I don't want developers to have to do any special formatting to use the widget. update: I just wanted to add the purpose of this is I want to add a click listener to be able to expand the elements under the li, However, since those elements are within the li the click listener will activate even when clicking on the children, So I want to attach it to the text instead, to do this the text needs to be targetable, which is why I want to wrap it in a div of it's own. So far I've come up with wrapping all the inner elements of the li in a div and then moving all inner dom elements back to the original parent. But this code is pretty heavy for something that might be much simpler and not require so much DOM manipulation. EDIT: Want to share the first pseudo alternative I came up with but I think it is very tasking for what I want to accomplish. var innerTextThing = $("ul.tree ul").parents("li").wrapInner("<div class='tree-node-text'>"); $(innerTextThing.find(".tree-node-text")).each(function(){ $(this).after($(this).children("ul")); }); Answered: I ended up doing the following, FYI i only have to worry about FF and IE compatibility so it's untested in other browsers. //this will wrap all li textNodes in a div so we can target them. $(that).find("li").contents() .filter(function () { return this.nodeType == 3; }).each(function () { if ( //these are for IE and FF compatibility (this.textContent != undefined && this.textContent.trim() != "") || (this.innerText != undefined && this.innerText.trim() != "") ) { $(this).wrap("<div class='tree-node-text'>"); } });

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How to optimize dynamic programming?

- by Chan

Problem A number is called lucky if the sum of its digits, as well as the sum of the squares of its digits is a prime number. How many numbers between A and B are lucky? Input: The first line contains the number of test cases T. Each of the next T lines contains two integers, A and B. Output: Output T lines, one for each case containing the required answer for the corresponding case. Constraints: 1 <= T <= 10000 1 <= A <= B <= 10^18 Sample Input: 2 1 20 120 130 Sample Output: 4 1 Explanation: For the first case, the lucky numbers are 11, 12, 14, 16. For the second case, the only lucky number is 120. The problem is quite simple if we use brute force, however the running time is so critical that my program failed most test cases. My current idea is to use dynamic programming by storing the previous sum in a temporary array, so for example: sum_digits(10) = 1 -> sum_digits(11) = sum_digits(10) + 1 The same idea is applied for sum square but with counter equals to odd numbers. Unfortunately, it still failed 9 of 10 test cases which makes me think there must be a better way to solve it. Any idea would be greatly appreciated. #include <iostream> #include <vector> #include <string> #include <algorithm> #include <unordered_map> #include <unordered_set> #include <cmath> #include <cassert> #include <bitset> using namespace std; bool prime_table[1540] = { 0, 0, 1, 1, 0, 1, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0 }; unsigned num_digits(long long i) { return i > 0 ? (long) log10 ((double) i) + 1 : 1; } void get_sum_and_sum_square_digits(long long n, int& sum, int& sum_square) { sum = 0; sum_square = 0; int digit; while (n) { digit = n % 10; sum += digit; sum_square += digit * digit; n /= 10; } } void init_digits(long long n, long long previous_sum[], const int size = 18) { int current_no_digits = num_digits(n); int digit; for (int i = 0; i < current_no_digits; ++i) { digit = n % 10; previous_sum[i] = digit; n /= 10; } for (int i = current_no_digits; i <= size; ++i) { previous_sum[i] = 0; } } void display_previous(long long previous[]) { for (int i = 0; i < 18; ++i) { cout << previous[i] << ","; } } int count_lucky_number(long long A, long long B) { long long n = A; long long end = B; int sum = 0; int sum_square = 0; int lucky_counter = 0; get_sum_and_sum_square_digits(n, sum, sum_square); long long sum_counter = sum; long long sum_square_counter = sum_square; if (prime_table[sum_counter] && prime_table[sum_square_counter]) { lucky_counter++; } long long previous_sum[19] = {1}; init_digits(n, previous_sum); while (n < end) { n++; if (n % 100000000000000000 == 0) { previous_sum[17]++; sum_counter = previous_sum[17] + previous_sum[18]; sum_square_counter = previous_sum[17] * previous_sum[17] + previous_sum[18] * previous_sum[18]; previous_sum[16] = 0; previous_sum[15] = 0; previous_sum[14] = 0; previous_sum[13] = 0; previous_sum[12] = 0; previous_sum[11] = 0; previous_sum[10] = 0; previous_sum[9] = 0; previous_sum[8] = 0; previous_sum[7] = 0; previous_sum[6] = 0; previous_sum[5] = 0; previous_sum[4] = 0; previous_sum[3] = 0; previous_sum[2] = 0; previous_sum[1] = 0; previous_sum[0] = 0; } else if (n % 10000000000000000 == 0) { previous_sum[16]++; sum_counter = previous_sum[16] + previous_sum[17] + previous_sum[18]; sum_square_counter = previous_sum[16] * previous_sum[16] + previous_sum[17] * previous_sum[17] + previous_sum[18] * previous_sum[18]; previous_sum[15] = 0; previous_sum[14] = 0; previous_sum[13] = 0; previous_sum[12] = 0; previous_sum[11] = 0; previous_sum[10] = 0; previous_sum[9] = 0; previous_sum[8] = 0; previous_sum[7] = 0; previous_sum[6] = 0; previous_sum[5] = 0; previous_sum[4] = 0; previous_sum[3] = 0; previous_sum[2] = 0; previous_sum[1] = 0; previous_sum[0] = 0; } else if (n % 1000000000000000 == 0) { previous_sum[15]++; sum_counter = previous_sum[15] + previous_sum[16] + previous_sum[17] + previous_sum[18]; sum_square_counter = previous_sum[15] * previous_sum[15] + previous_sum[16] * previous_sum[16] + previous_sum[17] * previous_sum[17] + previous_sum[18] * previous_sum[18]; previous_sum[14] = 0; previous_sum[13] = 0; previous_sum[12] = 0; previous_sum[11] = 0; previous_sum[10] = 0; previous_sum[9] = 0; previous_sum[8] = 0; previous_sum[7] = 0; previous_sum[6] = 0; previous_sum[5] = 0; previous_sum[4] = 0; previous_sum[3] = 0; previous_sum[2] = 0; previous_sum[1] = 0; previous_sum[0] = 0; } else if (n % 100000000000000 == 0) { previous_sum[14]++; sum_counter = previous_sum[14] + previous_sum[15] + previous_sum[16] + previous_sum[17] + previous_sum[18]; sum_square_counter = previous_sum[14] * previous_sum[14] + previous_sum[15] * previous_sum[15] + previous_sum[16] * previous_sum[16] + previous_sum[17] * previous_sum[17] + previous_sum[18] * previous_sum[18]; previous_sum[13] = 0; previous_sum[12] = 0; previous_sum[11] = 0; previous_sum[10] = 0; previous_sum[9] = 0; previous_sum[8] = 0; previous_sum[7] = 0; previous_sum[6] = 0; previous_sum[5] = 0; previous_sum[4] = 0; previous_sum[3] = 0; previous_sum[2] = 0; previous_sum[1] = 0; previous_sum[0] = 0; } else if (n % 10000000000000 == 0) { previous_sum[13]++; sum_counter = previous_sum[13] + previous_sum[14] + previous_sum[15] + previous_sum[16] + previous_sum[17] + previous_sum[18]; sum_square_counter = previous_sum[13] * previous_sum[13] + previous_sum[14] * previous_sum[14] + previous_sum[15] * previous_sum[15] + previous_sum[16] * previous_sum[16] + previous_sum[17] * previous_sum[17] + previous_sum[18] * previous_sum[18]; previous_sum[12] = 0; previous_sum[11] = 0; previous_sum[10] = 0; previous_sum[9] = 0; previous_sum[8] = 0; previous_sum[7] = 0; previous_sum[6] = 0; previous_sum[5] = 0; previous_sum[4] = 0; previous_sum[3] = 0; previous_sum[2] = 0; previous_sum[1] = 0; previous_sum[0] = 0; } else if (n % 1000000000000 == 0) { previous_sum[12]++; sum_counter = previous_sum[12] + previous_sum[13] + previous_sum[14] + previous_sum[15] + previous_sum[16] + previous_sum[17] + previous_sum[18]; sum_square_counter = previous_sum[12] * previous_sum[12] + previous_sum[13] * previous_sum[13] + previous_sum[14] * previous_sum[14] + previous_sum[15] * previous_sum[15] + previous_sum[16] * previous_sum[16] + previous_sum[17] * previous_sum[17] + previous_sum[18] * previous_sum[18]; previous_sum[11] = 0; previous_sum[10] = 0; previous_sum[9] = 0; previous_sum[8] = 0; previous_sum[7] = 0; previous_sum[6] = 0; previous_sum[5] = 0; previous_sum[4] = 0; previous_sum[3] = 0; previous_sum[2] = 0; previous_sum[1] = 0; previous_sum[0] = 0; } else if (n % 100000000000 == 0) { previous_sum[11]++; sum_counter = previous_sum[11] + previous_sum[12] + previous_sum[13] + previous_sum[14] + previous_sum[15] + previous_sum[16] + previous_sum[17] + previous_sum[18]; sum_square_counter = previous_sum[11] * previous_sum[11] + previous_sum[12] * previous_sum[12] + previous_sum[13] * previous_sum[13] + previous_sum[14] * previous_sum[14] + previous_sum[15] * previous_sum[15] + previous_sum[16] * previous_sum[16] + previous_sum[17] * previous_sum[17] + previous_sum[18] * previous_sum[18]; previous_sum[10] = 0; previous_sum[9] = 0; previous_sum[8] = 0; previous_sum[7] = 0; previous_sum[6] = 0; previous_sum[5] = 0; previous_sum[4] = 0; previous_sum[3] = 0; previous_sum[2] = 0; previous_sum[1] = 0; previous_sum[0] = 0; } else if (n % 10000000000 == 0) { previous_sum[10]++; sum_counter = previous_sum[10] + previous_sum[11] + previous_sum[12] + previous_sum[13] + previous_sum[14] + previous_sum[15] + previous_sum[16] + previous_sum[17] + previous_sum[18]; sum_square_counter = previous_sum[10] * previous_sum[10] + previous_sum[11] * previous_sum[11] + previous_sum[12] * previous_sum[12] + previous_sum[13] * previous_sum[13] + previous_sum[14] * previous_sum[14] + previous_sum[15] * previous_sum[15] + previous_sum[16] * previous_sum[16] + previous_sum[17] * previous_sum[17] + previous_sum[18] * previous_sum[18]; previous_sum[9] = 0; previous_sum[8] = 0; previous_sum[7] = 0; previous_sum[6] = 0; previous_sum[5] = 0; previous_sum[4] = 0; previous_sum[3] = 0; previous_sum[2] = 0; previous_sum[1] = 0; previous_sum[0] = 0; } else if (n % 1000000000 == 0) { previous_sum[9]++; sum_counter = previous_sum[9] + previous_sum[10] + previous_sum[11] + previous_sum[12] + previous_sum[13] + previous_sum[14] + previous_sum[15] + previous_sum[16] + previous_sum[17] + previous_sum[18]; sum_square_counter = previous_sum[9] * previous_sum[9] + previous_sum[10] * previous_sum[10] + previous_sum[11] * previous_sum[11] + previous_sum[12] * previous_sum[12] + previous_sum[13] * previous_sum[13] + previous_sum[14] * previous_sum[14] + previous_sum[15] * previous_sum[15] + previous_sum[16] * previous_sum[16] + previous_sum[17] * previous_sum[17] + previous_sum[18] * previous_sum[18]; previous_sum[8] = 0; previous_sum[7] = 0; previous_sum[6] = 0; previous_sum[5] = 0; previous_sum[4] = 0; previous_sum[3] = 0; previous_sum[2] = 0; previous_sum[1] = 0; previous_sum[0] = 0; } else if (n % 100000000 == 0) { previous_sum[8]++; sum_counter = previous_sum[8] + previous_sum[9] + previous_sum[10] + previous_sum[11] + previous_sum[12] + previous_sum[13] + previous_sum[14] + previous_sum[15] + previous_sum[16] + previous_sum[17] + previous_sum[18]; sum_square_counter = previous_sum[8] * previous_sum[8] + previous_sum[9] * previous_sum[9] + previous_sum[10] * previous_sum[10] + previous_sum[11] * previous_sum[11] + previous_sum[12] * previous_sum[12] + previous_sum[13] * previous_sum[13] + previous_sum[14] * previous_sum[14] + previous_sum[15] * previous_sum[15] + previous_sum[16] * previous_sum[16] + previous_sum[17] * previous_sum[17] + previous_sum[18] * previous_sum[18]; previous_sum[7] = 0; previous_sum[6] = 0; previous_sum[5] = 0; previous_sum[4] = 0; previous_sum[3] = 0; previous_sum[2] = 0; previous_sum[1] = 0; previous_sum[0] = 0; } else if (n % 10000000 == 0) { previous_sum[7]++; sum_counter = previous_sum[7] + previous_sum[8] + previous_sum[9] + previous_sum[10] + previous_sum[11] + previous_sum[12] + previous_sum[13] + previous_sum[14] + previous_sum[15] + previous_sum[16] + previous_sum[17] + previous_sum[18]; sum_square_counter = previous_sum[7] * previous_sum[7] + previous_sum[8] * previous_sum[8] + previous_sum[9] * previous_sum[9] + previous_sum[10] * previous_sum[10] + previous_sum[11] * previous_sum[11] + previous_sum[12] * previous_sum[12] + previous_sum[13] * previous_sum[13] + previous_sum[14] * previous_sum[14] + previous_sum[15] * previous_sum[15] + previous_sum[16] * previous_sum[16] + previous_sum[17] * previous_sum[17] + previous_sum[18] * previous_sum[18]; previous_sum[6] = 0; previous_sum[5] = 0; previous_sum[4] = 0; previous_sum[3] = 0; previous_sum[2] = 0; previous_sum[1] = 0; previous_sum[0] = 0; } else if (n % 1000000 == 0) { previous_sum[6]++; sum_counter = previous_sum[6] + previous_sum[7] + previous_sum[8] + previous_sum[9] + previous_sum[10] + previous_sum[11] + previous_sum[12] + previous_sum[13] + previous_sum[14] + previous_sum[15] + previous_sum[16] + previous_sum[17] + previous_sum[18]; sum_square_counter = previous_sum[6] * previous_sum[6] + previous_sum[7] * previous_sum[7] + previous_sum[8] * previous_sum[8] + previous_sum[9] * previous_sum[9] + previous_sum[10] * previous_sum[10] + previous_sum[11] * previous_sum[11] + previous_sum[12] * previous_sum[12] + previous_sum[13] * previous_sum[13] + previous_sum[14] * previous_sum[14] + previous_sum[15] * previous_sum[15] + previous_sum[16] * previous_sum[16] + previous_sum[17] * previous_sum[17] + previous_sum[18] * previous_sum[18]; previous_sum[5] = 0; previous_sum[4] = 0; previous_sum[3] = 0; previous_sum[2] = 0; previous_sum[1] = 0; previous_sum[0] = 0; } else if (n % 100000 == 0) { previous_sum[5]++; sum_counter = previous_sum[5] + previous_sum[6] + previous_sum[7] + previous_sum[8] + previous_sum[9] + previous_sum[10] + previous_sum[11] + previous_sum[12] + previous_sum[13] + previous_sum[14] + previous_sum[15] + previous_sum[16] + previous_sum[17] + previous_sum[18]; sum_square_counter = previous_sum[5] * previous_sum[5] + previous_sum[6] * previous_sum[6] + previous_sum[7] * previous_sum[7] + previous_sum[8] * previous_sum[8] + previous_sum[9] * previous_sum[9] + previous_sum[10] * previous_sum[10] + previous_sum[11] * previous_sum[11] + previous_sum[12] * previous_sum[12] + previous_sum[13] * previous_sum[13] + previous_sum[14] * previous_sum[14] + previous_sum[15] * previous_sum[15] + previous_sum[16] * previous_sum[16] + previous_sum[17] * previous_sum[17] + previous_sum[18] * previous_sum[18]; previous_sum[4] = 0; previous_sum[3] = 0; previous_sum[2] = 0; previous_sum[1] = 0; previous_sum[0] = 0; } else if (n % 10000 == 0) { previous_sum[4]++; sum_counter = previous_sum[4] + previous_sum[5] + previous_sum[6] + previous_sum[7] + previous_sum[8] + previous_sum[9] + previous_sum[10] + previous_sum[11] + previous_sum[12] + previous_sum[13] + previous_sum[14] + previous_sum[15] + previous_sum[16] + previous_sum[17] + previous_sum[18]; sum_square_counter = previous_sum[4] * previous_sum[4] + previous_sum[5] * previous_sum[5] + previous_sum[6] * previous_sum[6] + previous_sum[7] * previous_sum[7] + previous_sum[8] * previous_sum[8] + previous_sum[9] * previous_sum[9] + previous_sum[12] * previous_sum[12] + previous_sum[13] * previous_sum[13] + previous_sum[14] * previous_sum[14] + previous_sum[15] * previous_sum[15] + previous_sum[16] * previous_sum[16] + previous_sum[17] * previous_sum[17] + previous_sum[18] * previous_sum[18]; previous_sum[3] = 0; previous_sum[2] = 0; previous_sum[1] = 0; previous_sum[0] = 0; } else if (n % 1000 == 0) { previous_sum[3]++; sum_counter = previous_sum[3] + previous_sum[4] + previous_sum[5] + previous_sum[6] + previous_sum[7] + previous_sum[8] + previous_sum[9] + previous_sum[10] + previous_sum[11] + previous_sum[12] + previous_sum[13] + previous_sum[14] + previous_sum[15] + previous_sum[16] + previous_sum[17] + previous_sum[18]; sum_square_counter = previous_sum[3] * previous_sum[3] + previous_sum[4] * previous_sum[4] + previous_sum[5] * previous_sum[5] + previous_sum[6] * previous_sum[6] + previous_sum[7] * previous_sum[7] + previous_sum[8] * previous_sum[8] + previous_sum[9] * previous_sum[9] + previous_sum[10] * previous_sum[10] + previous_sum[11] * previous_sum[11] + previous_sum[12] * previous_sum[12] + previous_sum[13] * previous_sum[13] + previous_sum[14] * previous_sum[14] + previous_sum[15] * previous_sum[15] + previous_sum[16] * previous_sum[16] + previous_sum[17] * previous_sum[17] + previous_sum[18] * previous_sum[18]; previous_sum[2] = 0; previous_sum[1] = 0; previous_sum[0] = 0; } else if (n % 100 == 0) { previous_sum[2]++; sum_counter = previous_sum[2] + previous_sum[3] + previous_sum[4] + previous_sum[5] + previous_sum[6] + previous_sum[7] + previous_sum[8] + previous_sum[9] + previous_sum[10] + previous_sum[11] + previous_sum[12] + previous_sum[13] + previous_sum[14] + previous_sum[15] + previous_sum[16] + previous_sum[17] + previous_sum[18]; sum_square_counter = previous_sum[2] * previous_sum[2] + previous_sum[3] * previous_sum[3] + previous_sum[4] * previous_sum[4] + previous_sum[5] * previous_sum[5] + previous_sum[6] * previous_sum[6] + previous_sum[7] * previous_sum[7] + previous_sum[8] * previous_sum[8] + previous_sum[9] * previous_sum[9] + previous_sum[10] * previous_sum[10] + previous_sum[11] * previous_sum[11] + previous_sum[12] * previous_sum[12] + previous_sum[13] * previous_sum[13] + previous_sum[14] * previous_sum[14] + previous_sum[15] * previous_sum[15] + previous_sum[16] * previous_sum[16] + previous_sum[17] * previous_sum[17] + previous_sum[18] * previous_sum[18]; previous_sum[1] = 0; previous_sum[0] = 0; } else if (n % 10 == 0) { previous_sum[1]++; sum_counter = previous_sum[1] + previous_sum[2] + previous_sum[3] + previous_sum[4] + previous_sum[5] + previous_sum[6] + previous_sum[7] + previous_sum[8] + previous_sum[9] + previous_sum[10] + previous_sum[11] + previous_sum[12] + previous_sum[13] + previous_sum[14] + previous_sum[15] + previous_sum[16] + previous_sum[17] + previous_sum[18]; sum_square_counter = previous_sum[1] * previous_sum[1] + previous_sum[2] * previous_sum[2] + previous_sum[3] * previous_sum[3] + previous_sum[4] * previous_sum[4] + previous_sum[5] * previous_sum[5] + previous_sum[6] * previous_sum[6] + previous_sum[7] * previous_sum[7] + previous_sum[8] * previous_sum[8] + previous_sum[9] * previous_sum[9] + previous_sum[10] * previous_sum[10] + previous_sum[11] * previous_sum[11] + previous_sum[12] * previous_sum[12] + previous_sum[13] * previous_sum[13] + previous_sum[14] * previous_sum[14] + previous_sum[15] * previous_sum[15] + previous_sum[16] * previous_sum[16] + previous_sum[17] * previous_sum[17] + previous_sum[18] * previous_sum[18]; previous_sum[0] = 0; } else { sum_counter++; sum_square_counter += ((n - 1) % 10) * 2 + 1; } // get_sum_and_sum_square_digits(n, sum, sum_square); // assert(sum == sum_counter && sum_square == sum_square_counter); if (prime_table[sum_counter] && prime_table[sum_square_counter]) { lucky_counter++; } } return lucky_counter; } void inout_lucky_numbers() { int n; cin >> n; long long a; long long b; while (n--) { cin >> a >> b; cout << count_lucky_number(a, b) << endl; } } int main() { inout_lucky_numbers(); return 0; }

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Form submission info showing up in URL and not working

- by kcurtin

I am making a Rails 3.1 app and have a signup form that was working fine, but I seemed to have changed something to break it.. I'm using Twitter bootstrap and twitter_bootstrap_form_for gem. I made some change that messed with the formatting of the form fields, but more importantly, when I submit the Sign Up form to create a new User, the information is showing up in the URL and looks like this: EDIT: This is happening in the latest versions of Chrome and Firefox http://localhost:3000/?utf8=%E2%9C%93&authenticity_token=UaKG5Y8fuPul2Klx7e2LtdPLTRepBxDM3Zdy8S%2F52W4%3D&user%5Bemail%5D=kevinc%40example.com&user%5Bpassword%5D=testing&user%5Bpassword_confirmation%5D=testing&commit=Sign+Up Here is the code for the form: <div class="span7"> <h3 class="center" id="more">Sign Up Now!</h3> <%= twitter_bootstrap_form_for @user do |user| %> <%= user.email_field :email, :placeholder => '[email protected]' %> <%= user.password_field :password %> <%= user.password_field :password_confirmation, 'Confirm Password' %> <%= user.actions do %> <%= user.submit 'Sign Up' %> <% end %> <% end %> </div> Here is the code for the UsersController: class UsersController < ApplicationController def new @user = User.new end def create @user = User.new(params[:user]) if @user.save redirect_to about_path, :notice => "Signed up!" else render 'new' end end end Not sure if there is more you need but if so let me know! Thank you! Edit: For debugging I tried specifying :post and also using a plain form_for <%= form_for(@user, :method => :post) do |f| %> <div class="field"> <%= f.label :email %> <%= f.email_field :email %> </div> <div class="field"> <%= f.label :password %> <%= f.password_field :password %> </div> <div class="field"> <%= f.label :password_confirmation %> <%= f.password_field :password_confirmation %> </div> <div class="actions"><%= f.submit "Sign Up" %></div> <% end %> This gives me the same problem as above. Adding routes.rb: Auth31::Application.routes.draw do get "home" => "pages#home" get "about" => "pages#about" get "contact" => "pages#contact" get "help" => "pages#help" get "login" => "sessions#new", :as => "login" get "logout" => "sessions#destroy", :as => "logout" get "signup" => "users#new", :as => "signup" root :to => "pages#home" resources :pages resources :users resources :sessions resources :password_resets end

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ASP.NET MVC Paging/Sorting/Filtering a list using ModelMetadata

- by rajbk

This post looks at how to control paging, sorting and filtering when displaying a list of data by specifying attributes in your Model using the ASP.NET MVC framework and the excellent MVCContrib library. It also shows how to hide/show columns and control the formatting of data using attributes. This uses the Northwind database. A sample project is attached at the end of this post. Let’s start by looking at a class called ProductViewModel. The properties in the class are decorated with attributes. The OrderBy attribute tells the system that the Model can be sorted using that property. The SearchFilter attribute tells the system that filtering is allowed on that property. Filtering type is set by the FilterType enum which currently supports Equals and Contains. The ScaffoldColumn property specifies if a column is hidden or not The DisplayFormat specifies how the data is formatted. public class ProductViewModel { [OrderBy(IsDefault = true)] [ScaffoldColumn(false)] public int? ProductID { get; set; } [SearchFilter(FilterType.Contains)] [OrderBy] [DisplayName("Product Name")] public string ProductName { get; set; } [OrderBy] [DisplayName("Unit Price")] [DisplayFormat(DataFormatString = "{0:c}")] public System.Nullable<decimal> UnitPrice { get; set; } [DisplayName("Category Name")] public string CategoryName { get; set; } [SearchFilter] [ScaffoldColumn(false)] public int? CategoryID { get; set; } [SearchFilter] [ScaffoldColumn(false)] public int? SupplierID { get; set; } [OrderBy] public bool Discontinued { get; set; } } Before we explore the code further, lets look at the UI. The UI has a section for filtering the data. The column headers with links are sortable. Paging is also supported with the help of a pager row. The pager is rendered using the MVCContrib Pager component. The data is displayed using a customized version of the MVCContrib Grid component. The customization was done in order for the Grid to be aware of the attributes mentioned above. Now, let’s look at what happens when we perform actions on this page. The diagram below shows the process: The form on the page has its method set to “GET” therefore we see all the parameters in the query string. The query string is shown in blue above. This query gets routed to an action called Index with parameters of type ProductViewModel and PageSortOptions. The parameters in the query string get mapped to the input parameters using model binding. The ProductView object created has the information needed to filter data while the PageAndSorting object is used for paging and sorting the data. The last block in the figure above shows how the filtered and paged list is created. We receive a product list from our product repository (which is of type IQueryable) and first filter it by calliing the AsFiltered extension method passing in the productFilters object and then call the AsPagination extension method passing in the pageSort object. The AsFiltered extension method looks at the type of the filter instance passed in. It skips properties in the instance that do not have the SearchFilter attribute. For properties that have the SearchFilter attribute, it adds filter expression trees to filter against the IQueryable data. The AsPagination extension method looks at the type of the IQueryable and ensures that the column being sorted on has the OrderBy attribute. If it does not find one, it looks for the default sort field [OrderBy(IsDefault = true)]. It is required that at least one attribute in your model has the [OrderBy(IsDefault = true)]. This because a person could be performing paging without specifying an order by column. As you may recall the LINQ Skip method now requires that you call an OrderBy method before it. Therefore we need a default order by column to perform paging. The extension method adds a order expressoin tree to the IQueryable and calls the MVCContrib AsPagination extension method to page the data. Implementation Notes Auto Postback The search filter region auto performs a get request anytime the dropdown selection is changed. This is implemented using the following jQuery snippet $(document).ready(function () { $("#productSearch").change(function () { this.submit(); }); }); Strongly Typed View The code used in the Action method is shown below: public ActionResult Index(ProductViewModel productFilters, PageSortOptions pageSortOptions) { var productPagedList = productRepository.GetProductsProjected().AsFiltered(productFilters).AsPagination(pageSortOptions); var productViewFilterContainer = new ProductViewFilterContainer(); productViewFilterContainer.Fill(productFilters.CategoryID, productFilters.SupplierID, productFilters.ProductName); var gridSortOptions = new GridSortOptions { Column = pageSortOptions.Column, Direction = pageSortOptions.Direction }; var productListContainer = new ProductListContainerModel { ProductPagedList = productPagedList, ProductViewFilterContainer = productViewFilterContainer, GridSortOptions = gridSortOptions }; return View(productListContainer); } As you see above, the object that is returned to the view is of type ProductListContainerModel. This contains all the information need for the view to render the Search filter section (including dropdowns), the Html.Pager (MVCContrib) and the Html.Grid (from MVCContrib). It also stores the state of the search filters so that they can recreate themselves when the page reloads (Viewstate, I miss you! :0) The class diagram for the container class is shown below. Custom MVCContrib Grid The MVCContrib grid default behavior was overridden so that it would auto generate the columns and format the columns based on the metadata and also make it aware of our custom attributes (see MetaDataGridModel in the sample code). The Grid ensures that the ShowForDisplay on the column is set to true This can also be set by the ScaffoldColumn attribute ref: http://bradwilson.typepad.com/blog/2009/10/aspnet-mvc-2-templates-part-2-modelmetadata.html) Column headers are set using the DisplayName attribute Column sorting is set using the OrderBy attribute. The data is formatted using the DisplayFormat attribute. Generic Extension methods for Sorting and Filtering The extension method AsFiltered takes in an IQueryable<T> and uses expression trees to query against the IQueryable data. The query is constructed using the Model metadata and the properties of the T filter (productFilters in our case). Properties in the Model that do not have the SearchFilter attribute are skipped when creating the filter expression tree. It returns an IQueryable<T>. The extension method AsPagination takes in an IQuerable<T> and first ensures that the column being sorted on has the OrderBy attribute. If not, we look for the default OrderBy column ([OrderBy(IsDefault = true)]). We then build an expression tree to sort on this column. We finally hand off the call to the MVCContrib AsPagination which returns an IPagination<T>. This type as you can see in the class diagram above is passed to the view and used by the MVCContrib Grid and Pager components. Custom Provider To get the system to recognize our custom attributes, we create our MetadataProvider as mentioned in this article (http://bradwilson.typepad.com/blog/2010/01/why-you-dont-need-modelmetadataattributes.html) protected override ModelMetadata CreateMetadata(IEnumerable<Attribute> attributes, Type containerType, Func<object> modelAccessor, Type modelType, string propertyName) { ModelMetadata metadata = base.CreateMetadata(attributes, containerType, modelAccessor, modelType, propertyName); SearchFilterAttribute searchFilterAttribute = attributes.OfType<SearchFilterAttribute>().FirstOrDefault(); if (searchFilterAttribute != null) { metadata.AdditionalValues.Add(Globals.SearchFilterAttributeKey, searchFilterAttribute); } OrderByAttribute orderByAttribute = attributes.OfType<OrderByAttribute>().FirstOrDefault(); if (orderByAttribute != null) { metadata.AdditionalValues.Add(Globals.OrderByAttributeKey, orderByAttribute); } return metadata; } We register our MetadataProvider in Global.asax.cs. protected void Application_Start() { AreaRegistration.RegisterAllAreas(); RegisterRoutes(RouteTable.Routes); ModelMetadataProviders.Current = new MvcFlan.QueryModelMetaDataProvider(); } Bugs, Comments and Suggestions are welcome! You can download the sample code below. This code is purely experimental. Use at your own risk. Download Sample Code (VS 2010 RTM) MVCNorthwindSales.zip

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Node.js Adventure - When Node Flying in Wind

- by Shaun

In the first post of this series I mentioned some popular modules in the community, such as underscore, async, etc.. I also listed a module named “Wind (zh-CN)”, which is created by one of my friend, Jeff Zhao (zh-CN). Now I would like to use a separated post to introduce this module since I feel it brings a new async programming style in not only Node.js but JavaScript world. If you know or heard about the new feature in C# 5.0 called “async and await”, or you learnt F#, you will find the “Wind” brings the similar async programming experience in JavaScript. By using “Wind”, we can write async code that looks like the sync code. The callbacks, async stats and exceptions will be handled by “Wind” automatically and transparently. What’s the Problem: Dense “Callback” Phobia Let’s firstly back to my second post in this series. As I mentioned in that post, when we wanted to read some records from SQL Server we need to open the database connection, and then execute the query. In Node.js all IO operation are designed as async callback pattern which means when the operation was done, it will invoke a function which was taken from the last parameter. For example the database connection opening code would be like this. 1: sql.open(connectionString, function(error, conn) { 2: if(error) { 3: // some error handling code 4: } 5: else { 6: // connection opened successfully 7: } 8: }); And then if we need to query the database the code would be like this. It nested in the previous function. 1: sql.open(connectionString, function(error, conn) { 2: if(error) { 3: // some error handling code 4: } 5: else { 6: // connection opened successfully 7: conn.queryRaw(command, function(error, results) { 8: if(error) { 9: // failed to execute this command 10: } 11: else { 12: // records retrieved successfully 13: } 14: }; 15: } 16: }); Assuming if we need to copy some data from this database to another then we need to open another connection and execute the command within the function under the query function. 1: sql.open(connectionString, function(error, conn) { 2: if(error) { 3: // some error handling code 4: } 5: else { 6: // connection opened successfully 7: conn.queryRaw(command, function(error, results) { 8: if(error) { 9: // failed to execute this command 10: } 11: else { 12: // records retrieved successfully 13: target.open(targetConnectionString, function(error, t_conn) { 14: if(error) { 15: // connect failed 16: } 17: else { 18: t_conn.queryRaw(copy_command, function(error, results) { 19: if(error) { 20: // copy failed 21: } 22: else { 23: // and then, what do you want to do now... 24: } 25: }; 26: } 27: }; 28: } 29: }; 30: } 31: }); This is just an example. In the real project the logic would be more complicated. This means our application might be messed up and the business process will be fragged by many callback functions. I would like call this “Dense Callback Phobia”. This might be a challenge how to make code straightforward and easy to read, something like below. 1: try 2: { 3: // open source connection 4: var s_conn = sqlConnect(s_connectionString); 5: // retrieve data 6: var results = sqlExecuteCommand(s_conn, s_command); 7: 8: // open target connection 9: var t_conn = sqlConnect(t_connectionString); 10: // prepare the copy command 11: var t_command = getCopyCommand(results); 12: // execute the copy command 13: sqlExecuteCommand(s_conn, t_command); 14: } 15: catch (ex) 16: { 17: // error handling 18: } What’s the Problem: Sync-styled Async Programming Similar as the previous problem, the callback-styled async programming model makes the upcoming operation as a part of the current operation, and mixed with the error handling code. So it’s very hard to understand what on earth this code will do. And since Node.js utilizes non-blocking IO mode, we cannot invoke those operations one by one, as they will be executed concurrently. For example, in this post when I tried to copy the records from Windows Azure SQL Database (a.k.a. WASD) to Windows Azure Table Storage, if I just insert the data into table storage one by one and then print the “Finished” message, I will see the message shown before the data had been copied. This is because all operations were executed at the same time. In order to make the copy operation and print operation executed synchronously I introduced a module named “async” and the code was changed as below. 1: async.forEach(results.rows, 2: function (row, callback) { 3: var resource = { 4: "PartitionKey": row[1], 5: "RowKey": row[0], 6: "Value": row[2] 7: }; 8: client.insertEntity(tableName, resource, function (error) { 9: if (error) { 10: callback(error); 11: } 12: else { 13: console.log("entity inserted."); 14: callback(null); 15: } 16: }); 17: }, 18: function (error) { 19: if (error) { 20: error["target"] = "insertEntity"; 21: res.send(500, error); 22: } 23: else { 24: console.log("all done."); 25: res.send(200, "Done!"); 26: } 27: }); It ensured that the “Finished” message will be printed when all table entities had been inserted. But it cannot promise that the records will be inserted in sequence. It might be another challenge to make the code looks like in sync-style? 1: try 2: { 3: forEach(row in rows) { 4: var entity = { /* ... */ }; 5: tableClient.insert(tableName, entity); 6: } 7: 8: console.log("Finished"); 9: } 10: catch (ex) { 11: console.log(ex); 12: } How “Wind” Helps “Wind” is a JavaScript library which provides the control flow with plain JavaScript for asynchronous programming (and more) without additional pre-compiling steps. It’s available in NPM so that we can install it through “npm install wind”. Now let’s create a very simple Node.js application as the example. This application will take some website URLs from the command arguments and tried to retrieve the body length and print them in console. Then at the end print “Finish”. I’m going to use “request” module to make the HTTP call simple so I also need to install by the command “npm install request”. The code would be like this. 1: var request = require("request"); 2: 3: // get the urls from arguments, the first two arguments are `node.exe` and `fetch.js` 4: var args = process.argv.splice(2); 5: 6: // main function 7: var main = function() { 8: for(var i = 0; i < args.length; i++) { 9: // get the url 10: var url = args[i]; 11: // send the http request and try to get the response and body 12: request(url, function(error, response, body) { 13: if(!error && response.statusCode == 200) { 14: // log the url and the body length 15: console.log( 16: "%s: %d.", 17: response.request.uri.href, 18: body.length); 19: } 20: else { 21: // log error 22: console.log(error); 23: } 24: }); 25: } 26: 27: // finished 28: console.log("Finished"); 29: }; 30: 31: // execute the main function 32: main(); Let’s execute this application. (I made them in multi-lines for better reading.) 1: node fetch.js 2: "http://www.igt.com/us-en.aspx" 3: "http://www.igt.com/us-en/games.aspx" 4: "http://www.igt.com/us-en/cabinets.aspx" 5: "http://www.igt.com/us-en/systems.aspx" 6: "http://www.igt.com/us-en/interactive.aspx" 7: "http://www.igt.com/us-en/social-gaming.aspx" 8: "http://www.igt.com/support.aspx" Below is the output. As you can see the finish message was printed at the beginning, and the pages’ length retrieved in a different order than we specified. This is because in this code the request command, console logging command are executed asynchronously and concurrently. Now let’s introduce “Wind” to make them executed in order, which means it will request the websites one by one, and print the message at the end. First of all we need to import the “Wind” package and make sure the there’s only one global variant named “Wind”, and ensure it’s “Wind” instead of “wind”. 1: var Wind = require("wind"); Next, we need to tell “Wind” which code will be executed asynchronously so that “Wind” can control the execution process. In this case the “request” operation executed asynchronously so we will create a “Task” by using a build-in helps function in “Wind” named Wind.Async.Task.create. 1: var requestBodyLengthAsync = function(url) { 2: return Wind.Async.Task.create(function(t) { 3: request(url, function(error, response, body) { 4: if(error || response.statusCode != 200) { 5: t.complete("failure", error); 6: } 7: else { 8: var data = 9: { 10: uri: response.request.uri.href, 11: length: body.length 12: }; 13: t.complete("success", data); 14: } 15: }); 16: }); 17: }; The code above created a “Task” from the original request calling code. In “Wind” a “Task” means an operation will be finished in some time in the future. A “Task” can be started by invoke its start() method, but no one knows when it actually will be finished. The Wind.Async.Task.create helped us to create a task. The only parameter is a function where we can put the actual operation in, and then notify the task object it’s finished successfully or failed by using the complete() method. In the code above I invoked the request method. If it retrieved the response successfully I set the status of this task as “success” with the URL and body length. If it failed I set this task as “failure” and pass the error out. Next, we will change the main() function. In “Wind” if we want a function can be controlled by Wind we need to mark it as “async”. This should be done by using the code below. 1: var main = eval(Wind.compile("async", function() { 2: })); When the application is running, Wind will detect “eval(Wind.compile(“async”, function” and generate an anonymous code from the body of this original function. Then the application will run the anonymous code instead of the original one. In our example the main function will be like this. 1: var main = eval(Wind.compile("async", function() { 2: for(var i = 0; i < args.length; i++) { 3: try 4: { 5: var result = $await(requestBodyLengthAsync(args[i])); 6: console.log( 7: "%s: %d.", 8: result.uri, 9: result.length); 10: } 11: catch (ex) { 12: console.log(ex); 13: } 14: } 15: 16: console.log("Finished"); 17: })); As you can see, when I tried to request the URL I use a new command named “$await”. It tells Wind, the operation next to $await will be executed asynchronously, and the main thread should be paused until it finished (or failed). So in this case, my application will be pause when the first response was received, and then print its body length, then try the next one. At the end, print the finish message. Finally, execute the main function. The full code would be like this. 1: var request = require("request"); 2: var Wind = require("wind"); 3: 4: var args = process.argv.splice(2); 5: 6: var requestBodyLengthAsync = function(url) { 7: return Wind.Async.Task.create(function(t) { 8: request(url, function(error, response, body) { 9: if(error || response.statusCode != 200) { 10: t.complete("failure", error); 11: } 12: else { 13: var data = 14: { 15: uri: response.request.uri.href, 16: length: body.length 17: }; 18: t.complete("success", data); 19: } 20: }); 21: }); 22: }; 23: 24: var main = eval(Wind.compile("async", function() { 25: for(var i = 0; i < args.length; i++) { 26: try 27: { 28: var result = $await(requestBodyLengthAsync(args[i])); 29: console.log( 30: "%s: %d.", 31: result.uri, 32: result.length); 33: } 34: catch (ex) { 35: console.log(ex); 36: } 37: } 38: 39: console.log("Finished"); 40: })); 41: 42: main().start(); Run our new application. At the beginning we will see the compiled and generated code by Wind. Then we can see the pages were requested one by one, and at the end the finish message was printed. Below is the code Wind generated for us. As you can see the original code, the output code were shown. 1: // Original: 2: function () { 3: for(var i = 0; i < args.length; i++) { 4: try 5: { 6: var result = $await(requestBodyLengthAsync(args[i])); 7: console.log( 8: "%s: %d.", 9: result.uri, 10: result.length); 11: } 12: catch (ex) { 13: console.log(ex); 14: } 15: } 16: 17: console.log("Finished"); 18: } 19: 20: // Compiled: 21: /* async << function () { */ (function () { 22: var _builder_$0 = Wind.builders["async"]; 23: return _builder_$0.Start(this, 24: _builder_$0.Combine( 25: _builder_$0.Delay(function () { 26: /* var i = 0; */ var i = 0; 27: /* for ( */ return _builder_$0.For(function () { 28: /* ; i < args.length */ return i < args.length; 29: }, function () { 30: /* ; i ++) { */ i ++; 31: }, 32: /* try { */ _builder_$0.Try( 33: _builder_$0.Delay(function () { 34: /* var result = $await(requestBodyLengthAsync(args[i])); */ return _builder_$0.Bind(requestBodyLengthAsync(args[i]), function (result) { 35: /* console.log("%s: %d.", result.uri, result.length); */ console.log("%s: %d.", result.uri, result.length); 36: return _builder_$0.Normal(); 37: }); 38: }), 39: /* } catch (ex) { */ function (ex) { 40: /* console.log(ex); */ console.log(ex); 41: return _builder_$0.Normal(); 42: /* } */ }, 43: null 44: ) 45: /* } */ ); 46: }), 47: _builder_$0.Delay(function () { 48: /* console.log("Finished"); */ console.log("Finished"); 49: return _builder_$0.Normal(); 50: }) 51: ) 52: ); 53: /* } */ }) How Wind Works Someone may raise a big concern when you find I utilized “eval” in my code. Someone may assume that Wind utilizes “eval” to execute some code dynamically while “eval” is very low performance. But I would say, Wind does NOT use “eval” to run the code. It only use “eval” as a flag to know which code should be compiled at runtime. When the code was firstly been executed, Wind will check and find “eval(Wind.compile(“async”, function”. So that it knows this function should be compiled. Then it utilized parse-js to analyze the inner JavaScript and generated the anonymous code in memory. Then it rewrite the original code so that when the application was running it will use the anonymous one instead of the original one. Since the code generation was done at the beginning of the application was started, in the future no matter how long our application runs and how many times the async function was invoked, it will use the generated code, no need to generate again. So there’s no significant performance hurt when using Wind. Wind in My Previous Demo Let’s adopt Wind into one of my previous demonstration and to see how it helps us to make our code simple, straightforward and easy to read and understand. In this post when I implemented the functionality that copied the records from my WASD to table storage, the logic would be like this. 1, Open database connection. 2, Execute a query to select all records from the table. 3, Recreate the table in Windows Azure table storage. 4, Create entities from each of the records retrieved previously, and then insert them into table storage. 5, Finally, show message as the HTTP response. But as the image below, since there are so many callbacks and async operations, it’s very hard to understand my logic from the code. Now let’s use Wind to rewrite our code. First of all, of course, we need the Wind package. Then we need to include the package files into project and mark them as “Copy always”. Add the Wind package into the source code. Pay attention to the variant name, you must use “Wind” instead of “wind”. 1: var express = require("express"); 2: var async = require("async"); 3: var sql = require("node-sqlserver"); 4: var azure = require("azure"); 5: var Wind = require("wind"); Now we need to create some async functions by using Wind. All async functions should be wrapped so that it can be controlled by Wind which are open database, retrieve records, recreate table (delete and create) and insert entity in table. Below are these new functions. All of them are created by using Wind.Async.Task.create. 1: sql.openAsync = function (connectionString) { 2: return Wind.Async.Task.create(function (t) { 3: sql.open(connectionString, function (error, conn) { 4: if (error) { 5: t.complete("failure", error); 6: } 7: else { 8: t.complete("success", conn); 9: } 10: }); 11: }); 12: }; 13: 14: sql.queryAsync = function (conn, query) { 15: return Wind.Async.Task.create(function (t) { 16: conn.queryRaw(query, function (error, results) { 17: if (error) { 18: t.complete("failure", error); 19: } 20: else { 21: t.complete("success", results); 22: } 23: }); 24: }); 25: }; 26: 27: azure.recreateTableAsync = function (tableName) { 28: return Wind.Async.Task.create(function (t) { 29: client.deleteTable(tableName, function (error, successful, response) { 30: console.log("delete table finished"); 31: client.createTableIfNotExists(tableName, function (error, successful, response) { 32: console.log("create table finished"); 33: if (error) { 34: t.complete("failure", error); 35: } 36: else { 37: t.complete("success", null); 38: } 39: }); 40: }); 41: }); 42: }; 43: 44: azure.insertEntityAsync = function (tableName, entity) { 45: return Wind.Async.Task.create(function (t) { 46: client.insertEntity(tableName, entity, function (error, entity, response) { 47: if (error) { 48: t.complete("failure", error); 49: } 50: else { 51: t.complete("success", null); 52: } 53: }); 54: }); 55: }; Then in order to use these functions we will create a new function which contains all steps for data copying. 1: var copyRecords = eval(Wind.compile("async", function (req, res) { 2: try { 3: } 4: catch (ex) { 5: console.log(ex); 6: res.send(500, "Internal error."); 7: } 8: })); Let’s execute steps one by one with the “$await” keyword introduced by Wind so that it will be invoked in sequence. First is to open the database connection. 1: var copyRecords = eval(Wind.compile("async", function (req, res) { 2: try { 3: // connect to the windows azure sql database 4: var conn = $await(sql.openAsync(connectionString)); 5: console.log("connection opened"); 6: } 7: catch (ex) { 8: console.log(ex); 9: res.send(500, "Internal error."); 10: } 11: })); Then retrieve all records from the database connection. 1: var copyRecords = eval(Wind.compile("async", function (req, res) { 2: try { 3: // connect to the windows azure sql database 4: var conn = $await(sql.openAsync(connectionString)); 5: console.log("connection opened"); 6: // retrieve all records from database 7: var results = $await(sql.queryAsync(conn, "SELECT * FROM [Resource]")); 8: console.log("records selected. count = %d", results.rows.length); 9: } 10: catch (ex) { 11: console.log(ex); 12: res.send(500, "Internal error."); 13: } 14: })); After recreated the table, we need to create the entities and insert them into table storage. 1: var copyRecords = eval(Wind.compile("async", function (req, res) { 2: try { 3: // connect to the windows azure sql database 4: var conn = $await(sql.openAsync(connectionString)); 5: console.log("connection opened"); 6: // retrieve all records from database 7: var results = $await(sql.queryAsync(conn, "SELECT * FROM [Resource]")); 8: console.log("records selected. count = %d", results.rows.length); 9: if (results.rows.length > 0) { 10: // recreate the table 11: $await(azure.recreateTableAsync(tableName)); 12: console.log("table created"); 13: // insert records in table storage one by one 14: for (var i = 0; i < results.rows.length; i++) { 15: var entity = { 16: "PartitionKey": results.rows[i][1], 17: "RowKey": results.rows[i][0], 18: "Value": results.rows[i][2] 19: }; 20: $await(azure.insertEntityAsync(tableName, entity)); 21: console.log("entity inserted"); 22: } 23: } 24: } 25: catch (ex) { 26: console.log(ex); 27: res.send(500, "Internal error."); 28: } 29: })); Finally, send response back to the browser. 1: var copyRecords = eval(Wind.compile("async", function (req, res) { 2: try { 3: // connect to the windows azure sql database 4: var conn = $await(sql.openAsync(connectionString)); 5: console.log("connection opened"); 6: // retrieve all records from database 7: var results = $await(sql.queryAsync(conn, "SELECT * FROM [Resource]")); 8: console.log("records selected. count = %d", results.rows.length); 9: if (results.rows.length > 0) { 10: // recreate the table 11: $await(azure.recreateTableAsync(tableName)); 12: console.log("table created"); 13: // insert records in table storage one by one 14: for (var i = 0; i < results.rows.length; i++) { 15: var entity = { 16: "PartitionKey": results.rows[i][1], 17: "RowKey": results.rows[i][0], 18: "Value": results.rows[i][2] 19: }; 20: $await(azure.insertEntityAsync(tableName, entity)); 21: console.log("entity inserted"); 22: } 23: // send response 24: console.log("all done"); 25: res.send(200, "All done!"); 26: } 27: } 28: catch (ex) { 29: console.log(ex); 30: res.send(500, "Internal error."); 31: } 32: })); If we compared with the previous code we will find now it became more readable and much easy to understand. It’s very easy to know what this function does even though without any comments. When user go to URL “/was/copyRecords” we will execute the function above. The code would be like this. 1: app.get("/was/copyRecords", function (req, res) { 2: copyRecords(req, res).start(); 3: }); And below is the logs printed in local compute emulator console. As we can see the functions executed one by one and then finally the response back to me browser. Scaffold Functions in Wind Wind provides not only the async flow control and compile functions, but many scaffold methods as well. We can build our async code more easily by using them. I’m going to introduce some basic scaffold functions here. In the code above I created some functions which wrapped from the original async function such as open database, create table, etc.. All of them are very similar, created a task by using Wind.Async.Task.create, return error or result object through Task.complete function. In fact, Wind provides some functions for us to create task object from the original async functions. If the original async function only has a callback parameter, we can use Wind.Async.Binding.fromCallback method to get the task object directly. For example the code below returned the task object which wrapped the file exist check function. 1: var Wind = require("wind"); 2: var fs = require("fs"); 3: 4: fs.existsAsync = Wind.Async.Binding.fromCallback(fs.exists); In Node.js a very popular async function pattern is that, the first parameter in the callback function represent the error object, and the other parameters is the return values. In this case we can use another build-in function in Wind named Wind.Async.Binding.fromStandard. For example, the open database function can be created from the code below. 1: sql.openAsync = Wind.Async.Binding.fromStandard(sql.open); 2: 3: /* 4: sql.openAsync = function (connectionString) { 5: return Wind.Async.Task.create(function (t) { 6: sql.open(connectionString, function (error, conn) { 7: if (error) { 8: t.complete("failure", error); 9: } 10: else { 11: t.complete("success", conn); 12: } 13: }); 14: }); 15: }; 16: */ When I was testing the scaffold functions under Wind.Async.Binding I found for some functions, such as the Azure SDK insert entity function, cannot be processed correctly. So I personally suggest writing the wrapped method manually. Another scaffold method in Wind is the parallel tasks coordination. In this example, the steps of open database, retrieve records and recreated table should be invoked one by one, but it can be executed in parallel when copying data from database to table storage. In Wind there’s a scaffold function named Task.whenAll which can be used here. Task.whenAll accepts a list of tasks and creates a new task. It will be returned only when all tasks had been completed, or any errors occurred. For example in the code below I used the Task.whenAll to make all copy operation executed at the same time. 1: var copyRecordsInParallel = eval(Wind.compile("async", function (req, res) { 2: try { 3: // connect to the windows azure sql database 4: var conn = $await(sql.openAsync(connectionString)); 5: console.log("connection opened"); 6: // retrieve all records from database 7: var results = $await(sql.queryAsync(conn, "SELECT * FROM [Resource]")); 8: console.log("records selected. count = %d", results.rows.length); 9: if (results.rows.length > 0) { 10: // recreate the table 11: $await(azure.recreateTableAsync(tableName)); 12: console.log("table created"); 13: // insert records in table storage in parallal 14: var tasks = new Array(results.rows.length); 15: for (var i = 0; i < results.rows.length; i++) { 16: var entity = { 17: "PartitionKey": results.rows[i][1], 18: "RowKey": results.rows[i][0], 19: "Value": results.rows[i][2] 20: }; 21: tasks[i] = azure.insertEntityAsync(tableName, entity); 22: } 23: $await(Wind.Async.Task.whenAll(tasks)); 24: // send response 25: console.log("all done"); 26: res.send(200, "All done!"); 27: } 28: } 29: catch (ex) { 30: console.log(ex); 31: res.send(500, "Internal error."); 32: } 33: })); 34: 35: app.get("/was/copyRecordsInParallel", function (req, res) { 36: copyRecordsInParallel(req, res).start(); 37: }); Besides the task creation and coordination, Wind supports the cancellation solution so that we can send the cancellation signal to the tasks. It also includes exception solution which means any exceptions will be reported to the caller function. Summary In this post I introduced a Node.js module named Wind, which created by my friend Jeff Zhao. As you can see, different from other async library and framework, adopted the idea from F# and C#, Wind utilizes runtime code generation technology to make it more easily to write async, callback-based functions in a sync-style way. By using Wind there will be almost no callback, and the code will be very easy to understand. Currently Wind is still under developed and improved. There might be some problems but the author, Jeff, should be very happy and enthusiastic to learn your problems, feedback, suggestion and comments. You can contact Jeff by - Email: [email protected] - Group: https://groups.google.com/d/forum/windjs - GitHub: https://github.com/JeffreyZhao/wind/issues Source code can be download here. Hope this helps, Shaun All documents and related graphics, codes are provided "AS IS" without warranty of any kind. Copyright © Shaun Ziyan Xu. This work is licensed under the Creative Commons License.

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A way of doing real-world test-driven development (and some thoughts about it)

- by Thomas Weller

Lately, I exchanged some arguments with Derick Bailey about some details of the red-green-refactor cycle of the Test-driven development process. In short, the issue revolved around the fact that it’s not enough to have a test red or green, but it’s also important to have it red or green for the right reasons. While for me, it’s sufficient to initially have a NotImplementedException in place, Derick argues that this is not totally correct (see these two posts: Red/Green/Refactor, For The Right Reasons and Red For The Right Reason: Fail By Assertion, Not By Anything Else). And he’s right. But on the other hand, I had no idea how his insights could have any practical consequence for my own individual interpretation of the red-green-refactor cycle (which is not really red-green-refactor, at least not in its pure sense, see the rest of this article). This made me think deeply for some days now. In the end I found out that the ‘right reason’ changes in my understanding depending on what development phase I’m in. To make this clear (at least I hope it becomes clear…) I started to describe my way of working in some detail, and then something strange happened: The scope of the article slightly shifted from focusing ‘only’ on the ‘right reason’ issue to something more general, which you might describe as something like 'Doing real-world TDD in .NET , with massive use of third-party add-ins’. This is because I feel that there is a more general statement about Test-driven development to make: It’s high time to speak about the ‘How’ of TDD, not always only the ‘Why’. Much has been said about this, and me myself also contributed to that (see here: TDD is not about testing, it's about how we develop software). But always justifying what you do is very unsatisfying in the long run, it is inherently defensive, and it costs time and effort that could be used for better and more important things. And frankly: I’m somewhat sick and tired of repeating time and again that the test-driven way of software development is highly preferable for many reasons - I don’t want to spent my time exclusively on stating the obvious… So, again, let’s say it clearly: TDD is programming, and programming is TDD. Other ways of programming (code-first, sometimes called cowboy-coding) are exceptional and need justification. – I know that there are many people out there who will disagree with this radical statement, and I also know that it’s not a description of the real world but more of a mission statement or something. But nevertheless I’m absolutely sure that in some years this statement will be nothing but a platitude. Side note: Some parts of this post read as if I were paid by Jetbrains (the manufacturer of the ReSharper add-in – R#), but I swear I’m not. Rather I think that Visual Studio is just not production-complete without it, and I wouldn’t even consider to do professional work without having this add-in installed... The three parts of a software component Before I go into some details, I first should describe my understanding of what belongs to a software component (assembly, type, or method) during the production process (i.e. the coding phase). Roughly, I come up with the three parts shown below: First, we need to have some initial sort of requirement. This can be a multi-page formal document, a vague idea in some programmer’s brain of what might be needed, or anything in between. In either way, there has to be some sort of requirement, be it explicit or not. – At the C# micro-level, the best way that I found to formulate that is to define interfaces for just about everything, even for internal classes, and to provide them with exhaustive xml comments. The next step then is to re-formulate these requirements in an executable form. This is specific to the respective programming language. - For C#/.NET, the Gallio framework (which includes MbUnit) in conjunction with the ReSharper add-in for Visual Studio is my toolset of choice. The third part then finally is the production code itself. It’s development is entirely driven by the requirements and their executable formulation. This is the delivery, the two other parts are ‘only’ there to make its production possible, to give it a decent quality and reliability, and to significantly reduce related costs down the maintenance timeline. So while the first two parts are not really relevant for the customer, they are very important for the developer. The customer (or in Scrum terms: the Product Owner) is not interested at all in how the product is developed, he is only interested in the fact that it is developed as cost-effective as possible, and that it meets his functional and non-functional requirements. The rest is solely a matter of the developer’s craftsmanship, and this is what I want to talk about during the remainder of this article… An example To demonstrate my way of doing real-world TDD, I decided to show the development of a (very) simple Calculator component. The example is deliberately trivial and silly, as examples always are. I am totally aware of the fact that real life is never that simple, but I only want to show some development principles here… The requirement As already said above, I start with writing down some words on the initial requirement, and I normally use interfaces for that, even for internal classes - the typical question “intf or not” doesn’t even come to mind. I need them for my usual workflow and using them automatically produces high componentized and testable code anyway. To think about their usage in every single situation would slow down the production process unnecessarily. So this is what I begin with: namespace Calculator { /// <summary> /// Defines a very simple calculator component for demo purposes. /// </summary> public interface ICalculator { /// <summary> /// Gets the result of the last successful operation. /// </summary> /// <value>The last result.</value> /// <remarks> /// Will be <see langword="null" /> before the first successful operation. /// </remarks> double? LastResult { get; } } // interface ICalculator } // namespace Calculator So, I’m not beginning with a test, but with a sort of code declaration - and still I insist on being 100% test-driven. There are three important things here: Starting this way gives me a method signature, which allows to use IntelliSense and AutoCompletion and thus eliminates the danger of typos - one of the most regular, annoying, time-consuming, and therefore expensive sources of error in the development process. In my understanding, the interface definition as a whole is more of a readable requirement document and technical documentation than anything else. So this is at least as much about documentation than about coding. The documentation must completely describe the behavior of the documented element. I normally use an IoC container or some sort of self-written provider-like model in my architecture. In either case, I need my components defined via service interfaces anyway. - I will use the LinFu IoC framework here, for no other reason as that is is very simple to use. The ‘Red’ (pt. 1) First I create a folder for the project’s third-party libraries and put the LinFu.Core dll there. Then I set up a test project (via a Gallio project template), and add references to the Calculator project and the LinFu dll. Finally I’m ready to write the first test, which will look like the following: namespace Calculator.Test { [TestFixture] public class CalculatorTest { private readonly ServiceContainer container = new ServiceContainer(); [Test] public void CalculatorLastResultIsInitiallyNull() { ICalculator calculator = container.GetService<ICalculator>(); Assert.IsNull(calculator.LastResult); } } // class CalculatorTest } // namespace Calculator.Test This is basically the executable formulation of what the interface definition states (part of). Side note: There’s one principle of TDD that is just plain wrong in my eyes: I’m talking about the Red is 'does not compile' thing. How could a compiler error ever be interpreted as a valid test outcome? I never understood that, it just makes no sense to me. (Or, in Derick’s terms: this reason is as wrong as a reason ever could be…) A compiler error tells me: Your code is incorrect, but nothing more. Instead, the ‘Red’ part of the red-green-refactor cycle has a clearly defined meaning to me: It means that the test works as intended and fails only if its assumptions are not met for some reason. Back to our Calculator. When I execute the above test with R#, the Gallio plugin will give me this output: So this tells me that the test is red for the wrong reason: There’s no implementation that the IoC-container could load, of course. So let’s fix that. With R#, this is very easy: First, create an ICalculator - derived type: Next, implement the interface members: And finally, move the new class to its own file: So far my ‘work’ was six mouse clicks long, the only thing that’s left to do manually here, is to add the Ioc-specific wiring-declaration and also to make the respective class non-public, which I regularly do to force my components to communicate exclusively via interfaces: This is what my Calculator class looks like as of now: using System; using LinFu.IoC.Configuration; namespace Calculator { [Implements(typeof(ICalculator))] internal class Calculator : ICalculator { public double? LastResult { get { throw new NotImplementedException(); } } } } Back to the test fixture, we have to put our IoC container to work: [TestFixture] public class CalculatorTest { #region Fields private readonly ServiceContainer container = new ServiceContainer(); #endregion // Fields #region Setup/TearDown [FixtureSetUp] public void FixtureSetUp() { container.LoadFrom(AppDomain.CurrentDomain.BaseDirectory, "Calculator.dll"); } ... Because I have a R# live template defined for the setup/teardown method skeleton as well, the only manual coding here again is the IoC-specific stuff: two lines, not more… The ‘Red’ (pt. 2) Now, the execution of the above test gives the following result: This time, the test outcome tells me that the method under test is called. And this is the point, where Derick and I seem to have somewhat different views on the subject: Of course, the test still is worthless regarding the red/green outcome (or: it’s still red for the wrong reasons, in that it gives a false negative). But as far as I am concerned, I’m not really interested in the test outcome at this point of the red-green-refactor cycle. Rather, I only want to assert that my test actually calls the right method. If that’s the case, I will happily go on to the ‘Green’ part… The ‘Green’ Making the test green is quite trivial. Just make LastResult an automatic property: [Implements(typeof(ICalculator))] internal class Calculator : ICalculator { public double? LastResult { get; private set; } } One more round… Now on to something slightly more demanding (cough…). Let’s state that our Calculator exposes an Add() method: ... /// <summary> /// Adds the specified operands. /// </summary> /// <param name="operand1">The operand1.</param> /// <param name="operand2">The operand2.</param> /// <returns>The result of the additon.</returns> /// <exception cref="ArgumentException"> /// Argument <paramref name="operand1"/> is < 0.<br/> /// -- or --<br/> /// Argument <paramref name="operand2"/> is < 0. /// </exception> double Add(double operand1, double operand2); } // interface ICalculator A remark: I sometimes hear the complaint that xml comment stuff like the above is hard to read. That’s certainly true, but irrelevant to me, because I read xml code comments with the CR_Documentor tool window. And using that, it looks like this: Apart from that, I’m heavily using xml code comments (see e.g. here for a detailed guide) because there is the possibility of automating help generation with nightly CI builds (using MS Sandcastle and the Sandcastle Help File Builder), and then publishing the results to some intranet location. This way, a team always has first class, up-to-date technical documentation at hand about the current codebase. (And, also very important for speeding up things and avoiding typos: You have IntelliSense/AutoCompletion and R# support, and the comments are subject to compiler checking…). Back to our Calculator again: Two more R# – clicks implement the Add() skeleton: ... public double Add(double operand1, double operand2) { throw new NotImplementedException(); } } // class Calculator As we have stated in the interface definition (which actually serves as our requirement document!), the operands are not allowed to be negative. So let’s start implementing that. Here’s the test: [Test] [Row(-0.5, 2)] public void AddThrowsOnNegativeOperands(double operand1, double operand2) { ICalculator calculator = container.GetService<ICalculator>(); Assert.Throws<ArgumentException>(() => calculator.Add(operand1, operand2)); } As you can see, I’m using a data-driven unit test method here, mainly for these two reasons: Because I know that I will have to do the same test for the second operand in a few seconds, I save myself from implementing another test method for this purpose. Rather, I only will have to add another Row attribute to the existing one. From the test report below, you can see that the argument values are explicitly printed out. This can be a valuable documentation feature even when everything is green: One can quickly review what values were tested exactly - the complete Gallio HTML-report (as it will be produced by the Continuous Integration runs) shows these values in a quite clear format (see below for an example). Back to our Calculator development again, this is what the test result tells us at the moment: So we’re red again, because there is not yet an implementation… Next we go on and implement the necessary parameter verification to become green again, and then we do the same thing for the second operand. To make a long story short, here’s the test and the method implementation at the end of the second cycle: // in CalculatorTest: [Test] [Row(-0.5, 2)] [Row(295, -123)] public void AddThrowsOnNegativeOperands(double operand1, double operand2) { ICalculator calculator = container.GetService<ICalculator>(); Assert.Throws<ArgumentException>(() => calculator.Add(operand1, operand2)); } // in Calculator: public double Add(double operand1, double operand2) { if (operand1 < 0.0) { throw new ArgumentException("Value must not be negative.", "operand1"); } if (operand2 < 0.0) { throw new ArgumentException("Value must not be negative.", "operand2"); } throw new NotImplementedException(); } So far, we have sheltered our method from unwanted input, and now we can safely operate on the parameters without further caring about their validity (this is my interpretation of the Fail Fast principle, which is regarded here in more detail). Now we can think about the method’s successful outcomes. First let’s write another test for that: [Test] [Row(1, 1, 2)] public void TestAdd(double operand1, double operand2, double expectedResult) { ICalculator calculator = container.GetService<ICalculator>(); double result = calculator.Add(operand1, operand2); Assert.AreEqual(expectedResult, result); } Again, I’m regularly using row based test methods for these kinds of unit tests. The above shown pattern proved to be extremely helpful for my development work, I call it the Defined-Input/Expected-Output test idiom: You define your input arguments together with the expected method result. There are two major benefits from that way of testing: In the course of refining a method, it’s very likely to come up with additional test cases. In our case, we might add tests for some edge cases like ‘one of the operands is zero’ or ‘the sum of the two operands causes an overflow’, or maybe there’s an external test protocol that has to be fulfilled (e.g. an ISO norm for medical software), and this results in the need of testing against additional values. In all these scenarios we only have to add another Row attribute to the test. Remember that the argument values are written to the test report, so as a side-effect this produces valuable documentation. (This can become especially important if the fulfillment of some sort of external requirements has to be proven). So your test method might look something like that in the end: [Test, Description("Arguments: operand1, operand2, expectedResult")] [Row(1, 1, 2)] [Row(0, 999999999, 999999999)] [Row(0, 0, 0)] [Row(0, double.MaxValue, double.MaxValue)] [Row(4, double.MaxValue - 2.5, double.MaxValue)] public void TestAdd(double operand1, double operand2, double expectedResult) { ICalculator calculator = container.GetService<ICalculator>(); double result = calculator.Add(operand1, operand2); Assert.AreEqual(expectedResult, result); } And this will produce the following HTML report (with Gallio): Not bad for the amount of work we invested in it, huh? - There might be scenarios where reports like that can be useful for demonstration purposes during a Scrum sprint review… The last requirement to fulfill is that the LastResult property is expected to store the result of the last operation. I don’t show this here, it’s trivial enough and brings nothing new… And finally: Refactor (for the right reasons) To demonstrate my way of going through the refactoring portion of the red-green-refactor cycle, I added another method to our Calculator component, namely Subtract(). Here’s the code (tests and production): // CalculatorTest.cs: [Test, Description("Arguments: operand1, operand2, expectedResult")] [Row(1, 1, 0)] [Row(0, 999999999, -999999999)] [Row(0, 0, 0)] [Row(0, double.MaxValue, -double.MaxValue)] [Row(4, double.MaxValue - 2.5, -double.MaxValue)] public void TestSubtract(double operand1, double operand2, double expectedResult) { ICalculator calculator = container.GetService<ICalculator>(); double result = calculator.Subtract(operand1, operand2); Assert.AreEqual(expectedResult, result); } [Test, Description("Arguments: operand1, operand2, expectedResult")] [Row(1, 1, 0)] [Row(0, 999999999, -999999999)] [Row(0, 0, 0)] [Row(0, double.MaxValue, -double.MaxValue)] [Row(4, double.MaxValue - 2.5, -double.MaxValue)] public void TestSubtractGivesExpectedLastResult(double operand1, double operand2, double expectedResult) { ICalculator calculator = container.GetService<ICalculator>(); calculator.Subtract(operand1, operand2); Assert.AreEqual(expectedResult, calculator.LastResult); } ... // ICalculator.cs: /// <summary> /// Subtracts the specified operands. /// </summary> /// <param name="operand1">The operand1.</param> /// <param name="operand2">The operand2.</param> /// <returns>The result of the subtraction.</returns> /// <exception cref="ArgumentException"> /// Argument <paramref name="operand1"/> is < 0.<br/> /// -- or --<br/> /// Argument <paramref name="operand2"/> is < 0. /// </exception> double Subtract(double operand1, double operand2); ... // Calculator.cs: public double Subtract(double operand1, double operand2) { if (operand1 < 0.0) { throw new ArgumentException("Value must not be negative.", "operand1"); } if (operand2 < 0.0) { throw new ArgumentException("Value must not be negative.", "operand2"); } return (this.LastResult = operand1 - operand2).Value; } Obviously, the argument validation stuff that was produced during the red-green part of our cycle duplicates the code from the previous Add() method. So, to avoid code duplication and minimize the number of code lines of the production code, we do an Extract Method refactoring. One more time, this is only a matter of a few mouse clicks (and giving the new method a name) with R#: Having done that, our production code finally looks like that: using System; using LinFu.IoC.Configuration; namespace Calculator { [Implements(typeof(ICalculator))] internal class Calculator : ICalculator { #region ICalculator public double? LastResult { get; private set; } public double Add(double operand1, double operand2) { ThrowIfOneOperandIsInvalid(operand1, operand2); return (this.LastResult = operand1 + operand2).Value; } public double Subtract(double operand1, double operand2) { ThrowIfOneOperandIsInvalid(operand1, operand2); return (this.LastResult = operand1 - operand2).Value; } #endregion // ICalculator #region Implementation (Helper) private static void ThrowIfOneOperandIsInvalid(double operand1, double operand2) { if (operand1 < 0.0) { throw new ArgumentException("Value must not be negative.", "operand1"); } if (operand2 < 0.0) { throw new ArgumentException("Value must not be negative.", "operand2"); } } #endregion // Implementation (Helper) } // class Calculator } // namespace Calculator But is the above worth the effort at all? It’s obviously trivial and not very impressive. All our tests were green (for the right reasons), and refactoring the code did not change anything. It’s not immediately clear how this refactoring work adds value to the project. Derick puts it like this: STOP! Hold on a second… before you go any further and before you even think about refactoring what you just wrote to make your test pass, you need to understand something: if your done with your requirements after making the test green, you are not required to refactor the code. I know… I’m speaking heresy, here. Toss me to the wolves, I’ve gone over to the dark side! Seriously, though… if your test is passing for the right reasons, and you do not need to write any test or any more code for you class at this point, what value does refactoring add? Derick immediately answers his own question: So why should you follow the refactor portion of red/green/refactor? When you have added code that makes the system less readable, less understandable, less expressive of the domain or concern’s intentions, less architecturally sound, less DRY, etc, then you should refactor it. I couldn’t state it more precise. From my personal perspective, I’d add the following: You have to keep in mind that real-world software systems are usually quite large and there are dozens or even hundreds of occasions where micro-refactorings like the above can be applied. It’s the sum of them all that counts. And to have a good overall quality of the system (e.g. in terms of the Code Duplication Percentage metric) you have to be pedantic on the individual, seemingly trivial cases. My job regularly requires the reading and understanding of ‘foreign’ code. So code quality/readability really makes a HUGE difference for me – sometimes it can be even the difference between project success and failure… Conclusions The above described development process emerged over the years, and there were mainly two things that guided its evolution (you might call it eternal principles, personal beliefs, or anything in between): Test-driven development is the normal, natural way of writing software, code-first is exceptional. So ‘doing TDD or not’ is not a question. And good, stable code can only reliably be produced by doing TDD (yes, I know: many will strongly disagree here again, but I’ve never seen high-quality code – and high-quality code is code that stood the test of time and causes low maintenance costs – that was produced code-first…) It’s the production code that pays our bills in the end. (Though I have seen customers these days who demand an acceptance test battery as part of the final delivery. Things seem to go into the right direction…). The test code serves ‘only’ to make the production code work. But it’s the number of delivered features which solely counts at the end of the day - no matter how much test code you wrote or how good it is. With these two things in mind, I tried to optimize my coding process for coding speed – or, in business terms: productivity - without sacrificing the principles of TDD (more than I’d do either way…). As a result, I consider a ratio of about 3-5/1 for test code vs. production code as normal and desirable. In other words: roughly 60-80% of my code is test code (This might sound heavy, but that is mainly due to the fact that software development standards only begin to evolve. The entire software development profession is very young, historically seen; only at the very beginning, and there are no viable standards yet. If you think about software development as a kind of casting process, where the test code is the mold and the resulting production code is the final product, then the above ratio sounds no longer extraordinary…) Although the above might look like very much unnecessary work at first sight, it’s not. With the aid of the mentioned add-ins, doing all the above is a matter of minutes, sometimes seconds (while writing this post took hours and days…). The most important thing is to have the right tools at hand. Slow developer machines or the lack of a tool or something like that - for ‘saving’ a few 100 bucks - is just not acceptable and a very bad decision in business terms (though I quite some times have seen and heard that…). Production of high-quality products needs the usage of high-quality tools. This is a platitude that every craftsman knows… The here described round-trip will take me about five to ten minutes in my real-world development practice. I guess it’s about 30% more time compared to developing the ‘traditional’ (code-first) way. But the so manufactured ‘product’ is of much higher quality and massively reduces maintenance costs, which is by far the single biggest cost factor, as I showed in this previous post: It's the maintenance, stupid! (or: Something is rotten in developerland.). In the end, this is a highly cost-effective way of software development… But on the other hand, there clearly is a trade-off here: coding speed vs. code quality/later maintenance costs. The here described development method might be a perfect fit for the overwhelming majority of software projects, but there certainly are some scenarios where it’s not - e.g. if time-to-market is crucial for a software project. So this is a business decision in the end. It’s just that you have to know what you’re doing and what consequences this might have… Some last words First, I’d like to thank Derick Bailey again. His two aforementioned posts (which I strongly recommend for reading) inspired me to think deeply about my own personal way of doing TDD and to clarify my thoughts about it. I wouldn’t have done that without this inspiration. I really enjoy that kind of discussions… I agree with him in all respects. But I don’t know (yet?) how to bring his insights into the described production process without slowing things down. The above described method proved to be very “good enough” in my practical experience. But of course, I’m open to suggestions here… My rationale for now is: If the test is initially red during the red-green-refactor cycle, the ‘right reason’ is: it actually calls the right method, but this method is not yet operational. Later on, when the cycle is finished and the tests become part of the regular, automated Continuous Integration process, ‘red’ certainly must occur for the ‘right reason’: in this phase, ‘red’ MUST mean nothing but an unfulfilled assertion - Fail By Assertion, Not By Anything Else!

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Ajax Control Toolkit May 2012 Release

- by Stephen.Walther

I’m happy to announce the May 2012 release of the Ajax Control Toolkit. This newest release of the Ajax Control Toolkit includes a new file upload control which displays file upload progress. We’ve also added several significant enhancements to the existing HtmlEditorExtender control such as support for uploading images and Source View. You can download and start using the newest version of the Ajax Control Toolkit by entering the following command in the Library Package Manager console in Visual Studio: Install-Package AjaxControlToolkit Alternatively, you can download the latest version of the Ajax Control Toolkit from CodePlex: http://AjaxControlToolkit.CodePlex.com The New Ajax File Upload Control The most requested new feature for the Ajax Control Toolkit (according to the CodePlex Issue Tracker) has been support for file upload with progress. We worked hard over the last few months to create an entirely new file upload control which displays upload progress. Here is a sample which illustrates how you can use the new AjaxFileUpload control: <%@ Page Language="C#" AutoEventWireup="true" CodeBehind="01_FileUpload.aspx.cs" Inherits="WebApplication1._01_FileUpload" %> <html> <head runat="server"> <title>Simple File Upload</title> </head> <body> <form id="form1" runat="server"> <div> <ajaxToolkit:ToolkitScriptManager runat="server" /> <ajaxToolkit:AjaxFileUpload id="ajaxUpload1" OnUploadComplete="ajaxUpload1_OnUploadComplete" runat="server" /> </div> </form> </body> </html> The page above includes a ToolkitScriptManager control. This control is required to use any of the controls in the Ajax Control Toolkit because this control is responsible for loading all of the scripts required by a control. The page also contains an AjaxFileUpload control. The UploadComplete event is handled in the code-behind for the page: namespace WebApplication1 { public partial class _01_FileUpload : System.Web.UI.Page { protected void ajaxUpload1_OnUploadComplete(object sender, AjaxControlToolkit.AjaxFileUploadEventArgs e) { // Generate file path string filePath = "~/Images/" + e.FileName; // Save upload file to the file system ajaxUpload1.SaveAs(MapPath(filePath)); } } } The UploadComplete handler saves each uploaded file by calling the AjaxFileUpload control’s SaveAs() method with a full file path. Here’s a video which illustrates the process of uploading a file: Warning: in order to write to the Images folder on a production IIS server, you need Write permissions on the Images folder. You need to provide permissions for the IIS Application Pool account to write to the Images folder. To learn more, see: http://learn.iis.net/page.aspx/624/application-pool-identities/ Showing File Upload Progress The new AjaxFileUpload control takes advantage of HTML5 upload progress events (described in the XMLHttpRequest Level 2 standard). This standard is supported by Firefox 8+, Chrome 16+, Safari 5+, and Internet Explorer 10+. In other words, the standard is supported by the most recent versions of all browsers except for Internet Explorer which will support the standard with the release of Internet Explorer 10. The AjaxFileUpload control works with all browsers, even browsers which do not support the new XMLHttpRequest Level 2 standard. If you use the AjaxFileUpload control with a downlevel browser – such as Internet Explorer 9 — then you get a simple throbber image during a file upload instead of a progress indicator. Here’s how you specify a throbber image when declaring the AjaxFileUpload control: <%@ Page Language="C#" AutoEventWireup="true" CodeBehind="02_FileUpload.aspx.cs" Inherits="WebApplication1._02_FileUpload" %> <html> <head id="Head1" runat="server"> <title>File Upload with Throbber</title> </head> <body> <form id="form1" runat="server"> <div> <ajaxToolkit:ToolkitScriptManager ID="ToolkitScriptManager1" runat="server" /> <ajaxToolkit:AjaxFileUpload id="ajaxUpload1" OnUploadComplete="ajaxUpload1_OnUploadComplete" ThrobberID="MyThrobber" runat="server" /> <asp:Image id="MyThrobber" ImageUrl="ajax-loader.gif" Style="display:None" runat="server" /> </div> </form> </body> </html> Notice that the page above includes an image with the Id MyThrobber. This image is displayed while files are being uploaded. I use the website http://AjaxLoad.info to generate animated busy wait images. Drag-And-Drop File Upload If you are using an uplevel browser then you can drag-and-drop the files which you want to upload onto the AjaxFileUpload control. The following video illustrates how drag-and-drop works: Remember that drag-and-drop will not work on Internet Explorer 9 or older. Accepting Multiple Files By default, the AjaxFileUpload control enables you to upload multiple files at a time. When you open the file dialog, use the CTRL or SHIFT key to select multiple files. If you want to restrict the number of files that can be uploaded then use the MaximumNumberOfFiles property like this: <ajaxToolkit:AjaxFileUpload id="ajaxUpload1" OnUploadComplete="ajaxUpload1_OnUploadComplete" ThrobberID="throbber" MaximumNumberOfFiles="1" runat="server" /> In the code above, the maximum number of files which can be uploaded is restricted to a single file. Restricting Uploaded File Types You might want to allow only certain types of files to be uploaded. For example, you might want to accept only image uploads. In that case, you can use the AllowedFileTypes property to provide a list of allowed file types like this: <ajaxToolkit:AjaxFileUpload id="ajaxUpload1" OnUploadComplete="ajaxUpload1_OnUploadComplete" ThrobberID="throbber" AllowedFileTypes="jpg,jpeg,gif,png" runat="server" /> The code above prevents any files except jpeg, gif, and png files from being uploaded. Enhancements to the HTMLEditorExtender Over the past months, we spent a considerable amount of time making bug fixes and feature enhancements to the existing HtmlEditorExtender control. I want to focus on two of the most significant enhancements that we made to the control: support for Source View and support for uploading images. Adding Source View Support to the HtmlEditorExtender When you click the Source View tag, the HtmlEditorExtender changes modes and displays the HTML source of the contents contained in the TextBox being extended. You can use Source View to make fine-grain changes to HTML before submitting the HTML to the server. For reasons of backwards compatibility, the Source View tab is disabled by default. To enable Source View, you need to declare your HtmlEditorExtender with the DisplaySourceTab property like this: <%@ Page Language="C#" AutoEventWireup="true" CodeBehind="05_SourceView.aspx.cs" Inherits="WebApplication1._05_SourceView" %> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html> <head id="Head1" runat="server"> <title>HtmlEditorExtender with Source View</title> </head> <body> <form id="form1" runat="server"> <div> <ajaxToolkit:ToolkitScriptManager ID="ToolkitScriptManager1" runat="server" /> <asp:TextBox id="txtComments" TextMode="MultiLine" Columns="60" Rows="10" Runat="server" /> <ajaxToolkit:HtmlEditorExtender id="HEE1" TargetControlID="txtComments" DisplaySourceTab="true" runat="server" /> </div> </form> </body> </html> The page above includes a ToolkitScriptManager, TextBox, and HtmlEditorExtender control. The HtmlEditorExtender extends the TextBox so that it supports rich text editing. Notice that the HtmlEditorExtender includes a DisplaySourceTab property. This property causes a button to appear at the bottom of the HtmlEditorExtender which enables you to switch to Source View: Note: when using the HtmlEditorExtender, we recommend that you set the DOCTYPE for the document. Otherwise, you can encounter weird formatting issues. Accepting Image Uploads We also enhanced the HtmlEditorExtender to support image uploads (another very highly requested feature at CodePlex). The following video illustrates the experience of adding an image to the editor: Once again, for backwards compatibility reasons, support for image uploads is disabled by default. Here’s how you can declare the HtmlEditorExtender so that it supports image uploads: <ajaxToolkit:HtmlEditorExtender id="MyHtmlEditorExtender" TargetControlID="txtComments" OnImageUploadComplete="MyHtmlEditorExtender_ImageUploadComplete" DisplaySourceTab="true" runat="server" > <Toolbar> <ajaxToolkit:Bold /> <ajaxToolkit:Italic /> <ajaxToolkit:Underline /> <ajaxToolkit:InsertImage /> </Toolbar> </ajaxToolkit:HtmlEditorExtender> There are two things that you should notice about the code above. First, notice that an InsertImage toolbar button is added to the HtmlEditorExtender toolbar. This HtmlEditorExtender will render toolbar buttons for bold, italic, underline, and insert image. Second, notice that the HtmlEditorExtender includes an event handler for the ImageUploadComplete event. The code for this event handler is below: using System.Web.UI; using AjaxControlToolkit; namespace WebApplication1 { public partial class _06_ImageUpload : System.Web.UI.Page { protected void MyHtmlEditorExtender_ImageUploadComplete(object sender, AjaxFileUploadEventArgs e) { // Generate file path string filePath = "~/Images/" + e.FileName; // Save uploaded file to the file system var ajaxFileUpload = (AjaxFileUpload)sender; ajaxFileUpload.SaveAs(MapPath(filePath)); // Update client with saved image path e.PostedUrl = Page.ResolveUrl(filePath); } } } Within the ImageUploadComplete event handler, you need to do two things: 1) Save the uploaded image (for example, to the file system, a database, or Azure storage) 2) Provide the URL to the saved image so the image can be displayed within the HtmlEditorExtender In the code above, the uploaded image is saved to the ~/Images folder. The path of the saved image is returned to the client by setting the AjaxFileUploadEventArgs PostedUrl property. Not surprisingly, under the covers, the HtmlEditorExtender uses the AjaxFileUpload. You can get a direct reference to the AjaxFileUpload control used by an HtmlEditorExtender by using the following code: void Page_Load() { var ajaxFileUpload = MyHtmlEditorExtender.AjaxFileUpload; ajaxFileUpload.AllowedFileTypes = "jpg,jpeg"; } The code above illustrates how you can restrict the types of images that can be uploaded to the HtmlEditorExtender. This code prevents anything but jpeg images from being uploaded. Summary This was the most difficult release of the Ajax Control Toolkit to date. We iterated through several designs for the AjaxFileUpload control – with each iteration, the goal was to make the AjaxFileUpload control easier for developers to use. My hope is that we were able to create a control which Web Forms developers will find very intuitive. I want to thank the developers on the Superexpert.com team for their hard work on this release.

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CodePlex Daily Summary for Friday, April 30, 2010

CodePlex Daily Summary for Friday, April 30, 2010New ProjectsAcres2: This is the new hotnessAsoraX.de - AirlineTycoon: EntwicklungsPhase von AsoraX.deazshop: Ecommerce macros and user controls based on Commerce4Umbraco from Umbraco CMS Project.BioPhotoAnalyzer: Some exercises with F#, WPF and Mathematical methods for quantitative analysis of biological photos, such as those obtained from microscopy, PAGE etcCECS622 - Simulations - South Computing Center: This simulation will be used to study the traffic flow of the South Computing Center (SCC) on the UofL campus. Document.Viewer: Basic document viewer for Windows XP, Vista and Windows 7 that supports FlowDocument, Rich and Plan Text FormatsDotNetNuke 5 Thai Language Pack: DotNetNuke Thai Language PackDotNetNuke Skins Pack: We derive html/css template from www.freecsstemplates.org and apply to DotNetNuke 4 & 5 Skins Pack.Dynamics AX Business Intelligence: Sample code for creating and using Dynamics AX Business Intelligence Easy Chat: Very simple kind of chat; it got DOS interface. It's just to start the server start the client enter the IP, enter your name, and you're ready to go!Html Source Transmitter Control: This web control allows getting a source of a web page, that will displayed before submit. So, developer can store a view of the html page, that wa...HydroServer - CUAHSI Hydrologic Information System Server: HydroServer is a set of software applications for publishing hydrologic datasets on the Internet. HydroServer leverages commercial software such a...Lisp.NET: Lisp.NET is a project that demonstrates how the Embedded Common Lisp (ECL) environment can be loaded and used from .NET. This enables Common Lisp ...Live-Exchange Calendar Sync: Live - Exchange Calendar Sync synchronizes calendars of users between 2 Exchange servers (it can be Live Calendar also). It's developed in C#. It u...MaLoRT : Mac Lovin' RayTracer: RaytracerMojo Workflow Web UI: Mojo Workflow Web UIMoonRover - Enter Island: Simple Graphics consumer application that simulates Moon RoversMVC Music Store: MVC Music Store is a tutorial application built on ASP.NET MVC 2. It's a lightweight sample store which sells albums online, demonstrating ASP.NET ...OpenPOS: OpenPOS, a completely open and free point-of-sale systemPgcDemuxCLI: A modified version of PgcDemux (http://download.videohelp.com/jsoto/dvdtools.htm) that has better CLI support and progress reporting.Sample 01: basic summarySharedEx: App dev in VS2010 RTM and Silverlight 4.0 for Windows Phone 7!SharePoint 2010 Managed Metadata WebPart: This SharePoint 2010 webpart creates a navigation control from a Managed Metadata column assigned to a list/library. The Termset the column relates...SharePoint 2010 Service Manager: The SharePoint Service manager let's you start and stop all the SharePoint 2010 services on your workstation. This is useful if you are running S...Sharp DOM: Sharp DOM is a view engine for ASP.NET MVC platform allowing developers to design extendable and maintenable dynamic HTML layouts using C# 4.0 lang...simple fx: simple framework written in javascriptSimpleGFC.NET: Simple GFC is a .NET library written in C# for simplifying the connection to Google Friend Connect. It is designed to be simple and concise, not a...SPSS & PSPP file library: Library for importing SPSS (now called PASW) & PSPP .sav datafiles, developed in C#. Support for writing and SPSS portable-files will be implemente...TailspinSpyworks - WebForms Sample Application: Tailspin Spyworks demonstrates how extraordinarily simple it is to create powerful, scalable applications for the .NET platform. It shows off how t...VividBed: Business website.卢融凯的个人主页: 卢融凯的个人主页New ReleasesAssemblyVerifier: 4.0.0.0 Release: Updated to target .NET 4.0Bricks' Bane: Bricks' Bane Editor v1.0.0.4: I've added functionality to the editor, after some personal use. Plus I fixed a bug that was occurring on file loading mostly when the file was mod...Dambach Linear Algebra Framework: Linear Algebra Framework - Sneak Peak: This is just to get the code out there into the hands of potential users and to elicit feedback.DevTreks -social budgeting that improves lives and livelihoods: Social Budgeting Web Software, DevTreks alpha 4a: DevTreks calculators, analyzers, and story tellers are being upgraded so that they can be extended by third parties using either add-ins (Managed ...DirectQ: Release 1.8.3c: Fixes some more late-breaking bugs and adds some optimizations from the forthcoming 1.8.4 release. No Windows 98 build this time. I may add one a...Document Assembly from a SharePoint Library using the Open XML SDK: Solution for March 2010 rel of the Open XML SDK: Microsoft changed some class names between the December 2009 CTP and the March 2010 release of the Open XML SDK which means that old solution will ...Document.Viewer: 0.9.0: Whats New?: New icon set Bug fix'sDotNetNuke Skins Pack: DNN 80 Skins Pack: This released is the first for DNN 4 & 5 with Skin Token Design (legacy skin support on DNN 4 & 5)DotNetWinService: Release 1.0.0.0: This release includes four different scheduled tasks: 1) TaskURL: Petition a specific URL: when working on a ASP.NET website, it's sometimes ...Hammock for REST: Hammock v1.0.1: v1.0.1 ChangesFixes to improve OAuth stability Fixes for asynchronous timeouts Fixes and simplification for retries v1.0 FeaturesSimple, clean...Home Access Plus+: v4.1.1: v4.1.1 Change Log: Added Enable for Booking Resource to allow Resources to be disabled but not deleted Updated HAP.Config for above File Changes...HouseFly controls: HouseFly controls alpha 0.9.6.0: HouseFly controls release 0.9.6.0 alphaHydroServer - CUAHSI Hydrologic Information System Server: ODM Data Loader 1.1.3: Version 1.1.3 of the ODM Data Loader is only compatible with version 1.1 of ODM This Version Addresses : Memory issues in Version 1.1.2 that were ...Jobping Url Shortener: Source Code v0.1: Source code for the 0.1 release.LinkedIn® for Windows Mobile: LinkedIn for Windows Mobile v0.6: Fixed the crash after accepting the use of internet access.mojoPortal: 2.3.4.3: see release notes on mojoportal.com http://www.mojoportal.com/mojoportal-2343-released.aspxMoonRover - Enter Island: Moon Rover: Simulates Rover Moves on MoonNanoPrompt: Release 0.4.1 - Beta 1.1: Now released: Beta 1.1 for .NET 4.0ORAYLIS BI.SmartDiff: Release 1.0.0: see change log for detailsQuickStart Engine (3D Game Engine for XNA): QuickStart Engine v0.22: Main FeaturesClean engine architecture Makes it easy to make your own game using the engine. Messaging system allows you to communicate between s...SharePoint 2010 Managed Metadata WebPart: Taxonomy WebPart 0.0.1: Initial version releasedSharePoint 2010 Service Manager: SharePoint Service Manager 2010 v1: Starts and stops all SharePoint services Works with both Microsoft SQL Server and SQL Server Express Edition (for SharePoint) Supports disablin...Shweet: SharePoint 2010 Team Messaging built with Pex: Shweet RTM Release: Shweet has been updated to work with the RTM of SharePoint and the latest version of Pex Visual Studio 2010 Power Tools. Know issues: Continuous I...Silverlight Testing Automation Tool: StatLight v1.0 - Beta 1: Things still to accomplish (before official v1 release)Item # 10716: Release build hangs on x64 machine Still awaiting UnitDriven change feedback...SPSS & PSPP file library: 0.1 alpha: This first test release allows to read an .sav SPSS/PSPP/PASW file and retreive the data, either in the form of a .net DataReader or as a custom Sp...SqlDiffFramework-A Visual Differencing Engine for Dissimilar Data Sources: SqlDiffFramework 1.0.0.0: Initial Public Release Requirements: .NET Framework 2.0 SqlDiffFramework is designed for the enterprise! Check with your system administrator (or...sqwarea: Sqwarea 0.0.210.0 (alpha): First public release. Deploy package contains : the documentation for classes. the azure package with the Web Role. the zip with assemblies wh...Sweeper: Sweeper Alpha 2: SweeperA Visual Studio Add-in for C# Code Formatting - Visual Studio 2008 Includes: A UI for options, Enable or disable any specific task you want ...TailspinSpyworks - WebForms Sample Application: TailspinSpyworks-v0.8: ASP.NET 4 ECommerce ApplicationTweetSharp: TweetSharp Release Candidate: New FeaturesComplete core rewrite for stability and speed, introducing Hammock http://hammock.codeplex.com Windows Phone 7, Silverlight 4 OOB (El...Wicked Compression ASP.NET HTTP Module: Wicked Compression ASP.NET HTTP Module Beta: Now supports AJAX from .NET Framework 2.0 through 4.0! Bug Fix for Excluded Paths! Binary Release Included for .NET Framework 2.0 through 4.0!Most Popular ProjectsRawrWBFS ManagerAJAX Control Toolkitpatterns & practices – Enterprise LibraryMicrosoft SQL Server Product Samples: DatabaseSilverlight ToolkitWindows Presentation Foundation (WPF)iTuner - The iTunes CompanionASP.NETDotNetNuke® Community EditionMost Active ProjectsRawrpatterns & practices – Enterprise LibraryIonics Isapi Rewrite FilterHydroServer - CUAHSI Hydrologic Information System ServerGMap.NET - Great Maps for Windows Forms & PresentationParticle Plot Pivotpatterns & practices: Azure Security GuidanceSqlDiffFramework-A Visual Differencing Engine for Dissimilar Data SourcesNB_Store - Free DotNetNuke Ecommerce Catalog ModuleN2 CMS

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Intermittent wired network issues in 14.04

- by Tommy Brunn

Since yesterday, my wired network connection has been dropping for a couple of seconds every 30 seconds or so. To my knowledge, I had not made any changes to my network. Output of ifconfig -a: ? ~ ifconfig -a eth0 Link encap:Ethernet HWaddr 6c:f0:49:b9:b1:7f inet addr:192.168.0.16 Bcast:192.168.0.255 Mask:255.255.255.0 inet6 addr: fe80::6ef0:49ff:feb9:b17f/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:11597 errors:0 dropped:0 overruns:0 frame:0 TX packets:9783 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:10101682 (10.1 MB) TX bytes:1215142 (1.2 MB) Interrupt:48 Base address:0x8000 lo Link encap:Local Loopback inet addr:127.0.0.1 Mask:255.0.0.0 inet6 addr: ::1/128 Scope:Host UP LOOPBACK RUNNING MTU:65536 Metric:1 RX packets:96691 errors:0 dropped:0 overruns:0 frame:0 TX packets:96691 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:13594355 (13.5 MB) TX bytes:13594355 (13.5 MB) lspci |grep Ethernet: 04:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller (rev 03) Pinging my router: ? ~ ping 192.168.0.1 PING 192.168.0.1 (192.168.0.1) 56(84) bytes of data. 64 bytes from 192.168.0.1: icmp_seq=1 ttl=64 time=0.435 ms 64 bytes from 192.168.0.1: icmp_seq=2 ttl=64 time=0.571 ms ping: sendmsg: Network is unreachable ping: sendmsg: Network is unreachable ping: sendmsg: Network is unreachable ping: sendmsg: Network is unreachable ping: sendmsg: Network is unreachable 64 bytes from 192.168.0.1: icmp_seq=8 ttl=64 time=1.03 ms And the output of route: ? ~ route Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface default 192.168.0.1 0.0.0.0 UG 0 0 0 eth0 192.168.0.0 * 255.255.255.0 U 1 0 0 eth0 Some messages from /var/logs/syslog: ? ~ tail -f /var/log/syslog Jun 6 10:37:34 lolbox dhclient: RCV: Advertise message on eth0 from fe80::120d:7fff:fe97:9d54. Jun 6 10:37:34 lolbox dhclient: IA_NA status code NoAddrsAvail. Jun 6 10:37:37 lolbox dnsmasq[1138]: Maximum number of concurrent DNS queries reached (max: 150) Jun 6 10:37:37 lolbox dnsmasq[1362]: Maximum number of concurrent DNS queries reached (max: 150) Jun 6 10:37:39 lolbox dhclient: XMT: Solicit on eth0, interval 8660ms. Jun 6 10:37:39 lolbox dhclient: RCV: Advertise message on eth0 from fe80::120d:7fff:fe97:9d54. Jun 6 10:37:39 lolbox dhclient: IA_NA status code NoAddrsAvail. Jun 6 10:37:47 lolbox dhclient: XMT: Solicit on eth0, interval 16820ms. Jun 6 10:37:47 lolbox dhclient: RCV: Advertise message on eth0 from fe80::120d:7fff:fe97:9d54. Jun 6 10:37:47 lolbox dhclient: IA_NA status code NoAddrsAvail. Jun 6 10:38:04 lolbox dhclient: XMT: Solicit on eth0, interval 34410ms. Jun 6 10:38:04 lolbox dhclient: RCV: Advertise message on eth0 from fe80::120d:7fff:fe97:9d54. Jun 6 10:38:04 lolbox dhclient: IA_NA status code NoAddrsAvail. Jun 6 10:38:16 lolbox NetworkManager[862]: <warn> (eth0): DHCPv6 request timed out. Jun 6 10:38:16 lolbox NetworkManager[862]: <info> (eth0): canceled DHCP transaction, DHCP client pid 13045 Jun 6 10:38:16 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 4 of 5 (IPv6 Configure Timeout) scheduled... Jun 6 10:38:16 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 4 of 5 (IPv6 Configure Timeout) started... Jun 6 10:38:16 lolbox NetworkManager[862]: <info> (eth0): device state change: activated -> failed (reason 'ip-config-unavailable') [100 120 5] Jun 6 10:38:16 lolbox NetworkManager[862]: <info> NetworkManager state is now DISCONNECTED Jun 6 10:38:16 lolbox NetworkManager[862]: <warn> Activation (eth0) failed for connection 'Wired connection 1' Jun 6 10:38:16 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 4 of 5 (IPv6 Configure Timeout) complete. Jun 6 10:38:16 lolbox NetworkManager[862]: <info> (eth0): device state change: failed -> disconnected (reason 'none') [120 30 0] Jun 6 10:38:16 lolbox NetworkManager[862]: <info> (eth0): deactivating device (reason 'none') [0] Jun 6 10:37:34 lolbox whoopsie[1133]: online Jun 6 10:38:16 lolbox whoopsie[1133]: offline Jun 6 10:38:16 lolbox dbus[485]: [system] Activating service name='org.freedesktop.nm_dispatcher' (using servicehelper) Jun 6 10:38:16 lolbox dbus[485]: [system] Successfully activated service 'org.freedesktop.nm_dispatcher' Jun 6 10:38:16 lolbox NetworkManager[862]: <info> (eth0): canceled DHCP transaction, DHCP client pid 13044 Jun 6 10:38:16 lolbox NetworkManager[862]: <warn> DNS: plugin dnsmasq update failed Jun 6 10:38:16 lolbox NetworkManager[862]: <info> Removing DNS information from /sbin/resolvconf Jun 6 10:38:16 lolbox avahi-daemon[619]: Withdrawing address record for fe80::6ef0:49ff:feb9:b17f on eth0. Jun 6 10:38:16 lolbox avahi-daemon[619]: Leaving mDNS multicast group on interface eth0.IPv6 with address fe80::6ef0:49ff:feb9:b17f. Jun 6 10:38:16 lolbox avahi-daemon[619]: Interface eth0.IPv6 no longer relevant for mDNS. Jun 6 10:38:16 lolbox avahi-daemon[619]: Withdrawing address record for 192.168.0.16 on eth0. Jun 6 10:38:16 lolbox avahi-daemon[619]: Leaving mDNS multicast group on interface eth0.IPv4 with address 192.168.0.16. Jun 6 10:38:16 lolbox avahi-daemon[619]: Interface eth0.IPv4 no longer relevant for mDNS. Jun 6 10:38:16 lolbox dnsmasq[1362]: setting upstream servers from DBus Jun 6 10:38:17 lolbox avahi-daemon[619]: Joining mDNS multicast group on interface eth0.IPv6 with address fe80::6ef0:49ff:feb9:b17f. Jun 6 10:38:17 lolbox avahi-daemon[619]: New relevant interface eth0.IPv6 for mDNS. Jun 6 10:38:17 lolbox avahi-daemon[619]: Registering new address record for fe80::6ef0:49ff:feb9:b17f on eth0.*. Jun 6 10:38:18 lolbox dnsmasq[1138]: no servers found in /var/run/dnsmasq/resolv.conf, will retry Jun 6 10:38:18 lolbox NetworkManager[862]: <info> Auto-activating connection 'Wired connection 1'. Jun 6 10:38:18 lolbox NetworkManager[862]: <info> Activation (eth0) starting connection 'Wired connection 1' Jun 6 10:38:18 lolbox NetworkManager[862]: <info> (eth0): device state change: disconnected -> prepare (reason 'none') [30 40 0] Jun 6 10:38:18 lolbox NetworkManager[862]: <info> NetworkManager state is now CONNECTING Jun 6 10:38:18 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 1 of 5 (Device Prepare) scheduled... Jun 6 10:38:18 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 1 of 5 (Device Prepare) started... Jun 6 10:38:18 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 2 of 5 (Device Configure) scheduled... Jun 6 10:38:18 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 1 of 5 (Device Prepare) complete. Jun 6 10:38:18 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 2 of 5 (Device Configure) starting... Jun 6 10:38:18 lolbox NetworkManager[862]: <info> (eth0): device state change: prepare -> config (reason 'none') [40 50 0] Jun 6 10:38:18 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 2 of 5 (Device Configure) successful. Jun 6 10:38:18 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 3 of 5 (IP Configure Start) scheduled. Jun 6 10:38:18 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 2 of 5 (Device Configure) complete. Jun 6 10:38:18 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 3 of 5 (IP Configure Start) started... Jun 6 10:38:18 lolbox NetworkManager[862]: <info> (eth0): device state change: config -> ip-config (reason 'none') [50 70 0] Jun 6 10:38:18 lolbox NetworkManager[862]: <info> Activation (eth0) Beginning DHCPv4 transaction (timeout in 45 seconds) Jun 6 10:38:18 lolbox NetworkManager[862]: <info> dhclient started with pid 13160 Jun 6 10:38:18 lolbox NetworkManager[862]: <info> Activation (eth0) Beginning DHCPv6 transaction (timeout in 45 seconds) Jun 6 10:38:18 lolbox NetworkManager[862]: <info> dhclient started with pid 13161 Jun 6 10:38:18 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 3 of 5 (IP Configure Start) complete. Jun 6 10:38:18 lolbox avahi-daemon[619]: Withdrawing address record for fe80::6ef0:49ff:feb9:b17f on eth0. Jun 6 10:38:18 lolbox avahi-daemon[619]: Leaving mDNS multicast group on interface eth0.IPv6 with address fe80::6ef0:49ff:feb9:b17f. Jun 6 10:38:18 lolbox avahi-daemon[619]: Interface eth0.IPv6 no longer relevant for mDNS. Jun 6 10:38:18 lolbox dhclient: Internet Systems Consortium DHCP Client 4.2.4 Jun 6 10:38:18 lolbox dhclient: Copyright 2004-2012 Internet Systems Consortium. Jun 6 10:38:18 lolbox dhclient: All rights reserved. Jun 6 10:38:18 lolbox dhclient: For info, please visit https://www.isc.org/software/dhcp/ Jun 6 10:38:18 lolbox dhclient: Jun 6 10:38:19 lolbox dhclient: Internet Systems Consortium DHCP Client 4.2.4 Jun 6 10:38:19 lolbox dhclient: Copyright 2004-2012 Internet Systems Consortium. Jun 6 10:38:19 lolbox dhclient: All rights reserved. Jun 6 10:38:19 lolbox dhclient: For info, please visit https://www.isc.org/software/dhcp/ Jun 6 10:38:19 lolbox dhclient: Jun 6 10:38:19 lolbox NetworkManager[862]: <info> (eth0): DHCPv4 state changed nbi -> preinit Jun 6 10:38:19 lolbox dhclient: Bound to *:546 Jun 6 10:38:19 lolbox dhclient: Listening on Socket/eth0 Jun 6 10:38:19 lolbox dhclient: Sending on Socket/eth0 Jun 6 10:38:19 lolbox NetworkManager[862]: <info> (eth0): DHCPv6 state changed nbi -> preinit6 Jun 6 10:38:19 lolbox dhclient: Listening on LPF/eth0/6c:f0:49:b9:b1:7f Jun 6 10:38:19 lolbox dhclient: Sending on LPF/eth0/6c:f0:49:b9:b1:7f Jun 6 10:38:19 lolbox dhclient: Sending on Socket/fallback Jun 6 10:38:19 lolbox dhclient: DHCPREQUEST of 192.168.0.16 on eth0 to 255.255.255.255 port 67 (xid=0x3fc9376d) Jun 6 10:38:19 lolbox dhclient: XMT: Solicit on eth0, interval 1020ms. Jun 6 10:38:19 lolbox dhclient: send_packet6: Cannot assign requested address Jun 6 10:38:19 lolbox dhclient: dhc6: send_packet6() sent -1 of 77 bytes Jun 6 10:38:20 lolbox dhclient: DHCPACK of 192.168.0.16 from 192.168.0.1 Jun 6 10:38:20 lolbox dhclient: bound to 192.168.0.16 -- renewal in 41481 seconds. Jun 6 10:38:20 lolbox NetworkManager[862]: <info> (eth0): DHCPv4 state changed preinit -> reboot Jun 6 10:38:20 lolbox NetworkManager[862]: <info> address 192.168.0.16 Jun 6 10:38:20 lolbox NetworkManager[862]: <info> prefix 24 (255.255.255.0) Jun 6 10:38:20 lolbox NetworkManager[862]: <info> gateway 192.168.0.1 Jun 6 10:38:20 lolbox NetworkManager[862]: <info> nameserver '83.255.245.11' Jun 6 10:38:20 lolbox NetworkManager[862]: <info> nameserver '193.150.193.150' Jun 6 10:38:20 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 5 of 5 (IPv4 Configure Commit) scheduled... Jun 6 10:38:20 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 5 of 5 (IPv4 Commit) started... Jun 6 10:38:20 lolbox avahi-daemon[619]: Joining mDNS multicast group on interface eth0.IPv4 with address 192.168.0.16. Jun 6 10:38:20 lolbox avahi-daemon[619]: New relevant interface eth0.IPv4 for mDNS. Jun 6 10:38:20 lolbox avahi-daemon[619]: Registering new address record for 192.168.0.16 on eth0.IPv4. Jun 6 10:38:20 lolbox dhclient: XMT: Solicit on eth0, interval 2110ms. Jun 6 10:38:20 lolbox dhclient: send_packet6: Cannot assign requested address Jun 6 10:38:20 lolbox dhclient: dhc6: send_packet6() sent -1 of 77 bytes Jun 6 10:38:20 lolbox avahi-daemon[619]: Joining mDNS multicast group on interface eth0.IPv6 with address fe80::6ef0:49ff:feb9:b17f. Jun 6 10:38:20 lolbox avahi-daemon[619]: New relevant interface eth0.IPv6 for mDNS. Jun 6 10:38:20 lolbox avahi-daemon[619]: Registering new address record for fe80::6ef0:49ff:feb9:b17f on eth0.*. Jun 6 10:38:21 lolbox NetworkManager[862]: <info> (eth0): device state change: ip-config -> secondaries (reason 'none') [70 90 0] Jun 6 10:38:21 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 5 of 5 (IPv4 Commit) complete. Jun 6 10:38:21 lolbox NetworkManager[862]: <info> (eth0): device state change: secondaries -> activated (reason 'none') [90 100 0] Jun 6 10:38:21 lolbox NetworkManager[862]: <info> NetworkManager state is now CONNECTED_GLOBAL Jun 6 10:38:21 lolbox NetworkManager[862]: <info> Policy set 'Wired connection 1' (eth0) as default for IPv4 routing and DNS. Jun 6 10:38:21 lolbox NetworkManager[862]: <info> Writing DNS information to /sbin/resolvconf Jun 6 10:38:21 lolbox dnsmasq[1362]: setting upstream servers from DBus Jun 6 10:38:21 lolbox dnsmasq[1362]: using nameserver 127.0.0.1#53 Jun 6 10:38:21 lolbox dnsmasq[1362]: using nameserver 193.150.193.150#53 Jun 6 10:38:21 lolbox dnsmasq[1362]: using nameserver 83.255.245.11#53 Jun 6 10:38:21 lolbox NetworkManager[862]: <info> Activation (eth0) successful, device activated. Jun 6 10:38:21 lolbox whoopsie[1133]: message repeated 2 times: [ offline] Jun 6 10:38:21 lolbox whoopsie[1133]: online Jun 6 10:38:21 lolbox ntpdate[13217]: Can't find host ntp.ubuntu.com: Name or service not known (-2) Jun 6 10:38:21 lolbox ntpdate[13217]: no servers can be used, exiting Jun 6 10:38:22 lolbox dnsmasq[1138]: reading /var/run/dnsmasq/resolv.conf Jun 6 10:38:22 lolbox dnsmasq[1138]: using nameserver 127.0.1.1#53 Jun 6 10:38:22 lolbox dhclient: XMT: Solicit on eth0, interval 4080ms. Jun 6 10:38:22 lolbox dhclient: RCV: Advertise message on eth0 from fe80::120d:7fff:fe97:9d54. Jun 6 10:38:22 lolbox dhclient: IA_NA status code NoAddrsAvail. Jun 6 10:38:26 lolbox dhclient: XMT: Solicit on eth0, interval 8450ms. Jun 6 10:38:26 lolbox dhclient: RCV: Advertise message on eth0 from fe80::120d:7fff:fe97:9d54. Jun 6 10:38:26 lolbox dhclient: IA_NA status code NoAddrsAvail. Jun 6 10:38:35 lolbox dhclient: XMT: Solicit on eth0, interval 16630ms. Jun 6 10:38:35 lolbox dhclient: RCV: Advertise message on eth0 from fe80::120d:7fff:fe97:9d54. Jun 6 10:38:35 lolbox dhclient: IA_NA status code NoAddrsAvail. Jun 6 10:38:51 lolbox dhclient: XMT: Solicit on eth0, interval 34860ms. Jun 6 10:38:51 lolbox dhclient: RCV: Advertise message on eth0 from fe80::120d:7fff:fe97:9d54. Jun 6 10:38:51 lolbox dhclient: IA_NA status code NoAddrsAvail. Jun 6 10:38:58 lolbox dnsmasq[1138]: Maximum number of concurrent DNS queries reached (max: 150) Jun 6 10:38:58 lolbox dnsmasq[1362]: Maximum number of concurrent DNS queries reached (max: 150) Jun 6 10:39:04 lolbox NetworkManager[862]: <warn> (eth0): DHCPv6 request timed out. Jun 6 10:39:04 lolbox NetworkManager[862]: <info> (eth0): canceled DHCP transaction, DHCP client pid 13161 Jun 6 10:39:04 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 4 of 5 (IPv6 Configure Timeout) scheduled... Jun 6 10:39:04 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 4 of 5 (IPv6 Configure Timeout) started... Jun 6 10:39:04 lolbox NetworkManager[862]: <info> (eth0): device state change: activated -> failed (reason 'ip-config-unavailable') [100 120 5] Jun 6 10:39:04 lolbox NetworkManager[862]: <info> NetworkManager state is now DISCONNECTED Jun 6 10:39:04 lolbox NetworkManager[862]: <warn> Activation (eth0) failed for connection 'Wired connection 1' Jun 6 10:38:22 lolbox whoopsie[1133]: online Jun 6 10:39:04 lolbox whoopsie[1133]: offline Jun 6 10:39:04 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 4 of 5 (IPv6 Configure Timeout) complete. Jun 6 10:39:04 lolbox dbus[485]: [system] Activating service name='org.freedesktop.nm_dispatcher' (using servicehelper) Jun 6 10:39:04 lolbox NetworkManager[862]: <info> (eth0): device state change: failed -> disconnected (reason 'none') [120 30 0] Jun 6 10:39:04 lolbox NetworkManager[862]: <info> (eth0): deactivating device (reason 'none') [0] Jun 6 10:39:04 lolbox dbus[485]: [system] Successfully activated service 'org.freedesktop.nm_dispatcher' Jun 6 10:39:04 lolbox NetworkManager[862]: <info> (eth0): canceled DHCP transaction, DHCP client pid 13160 Jun 6 10:39:04 lolbox avahi-daemon[619]: Withdrawing address record for fe80::6ef0:49ff:feb9:b17f on eth0. Jun 6 10:39:04 lolbox avahi-daemon[619]: Leaving mDNS multicast group on interface eth0.IPv6 with address fe80::6ef0:49ff:feb9:b17f. Jun 6 10:39:04 lolbox avahi-daemon[619]: Interface eth0.IPv6 no longer relevant for mDNS. Jun 6 10:39:04 lolbox avahi-daemon[619]: Withdrawing address record for 192.168.0.16 on eth0. Jun 6 10:39:04 lolbox avahi-daemon[619]: Leaving mDNS multicast group on interface eth0.IPv4 with address 192.168.0.16. Jun 6 10:39:04 lolbox avahi-daemon[619]: Interface eth0.IPv4 no longer relevant for mDNS. Jun 6 10:39:04 lolbox NetworkManager[862]: <warn> DNS: plugin dnsmasq update failed Jun 6 10:39:04 lolbox NetworkManager[862]: <info> Removing DNS information from /sbin/resolvconf Jun 6 10:39:04 lolbox dnsmasq[1362]: setting upstream servers from DBus Jun 6 10:39:05 lolbox avahi-daemon[619]: Joining mDNS multicast group on interface eth0.IPv6 with address fe80::6ef0:49ff:feb9:b17f. Jun 6 10:39:05 lolbox avahi-daemon[619]: New relevant interface eth0.IPv6 for mDNS. Jun 6 10:39:05 lolbox avahi-daemon[619]: Registering new address record for fe80::6ef0:49ff:feb9:b17f on eth0.*. Jun 6 10:39:06 lolbox dnsmasq[1138]: no servers found in /var/run/dnsmasq/resolv.conf, will retry Jun 6 10:39:07 lolbox NetworkManager[862]: <info> Auto-activating connection 'Wired connection 1'. Jun 6 10:39:07 lolbox NetworkManager[862]: <info> Activation (eth0) starting connection 'Wired connection 1' Jun 6 10:39:07 lolbox NetworkManager[862]: <info> (eth0): device state change: disconnected -> prepare (reason 'none') [30 40 0] Jun 6 10:39:07 lolbox NetworkManager[862]: <info> NetworkManager state is now CONNECTING Jun 6 10:39:07 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 1 of 5 (Device Prepare) scheduled... Jun 6 10:39:07 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 1 of 5 (Device Prepare) started... Jun 6 10:39:07 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 2 of 5 (Device Configure) scheduled... Jun 6 10:39:07 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 1 of 5 (Device Prepare) complete. Jun 6 10:39:07 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 2 of 5 (Device Configure) starting... Jun 6 10:39:07 lolbox NetworkManager[862]: <info> (eth0): device state change: prepare -> config (reason 'none') [40 50 0] Jun 6 10:39:07 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 2 of 5 (Device Configure) successful. Jun 6 10:39:07 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 3 of 5 (IP Configure Start) scheduled. Jun 6 10:39:07 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 2 of 5 (Device Configure) complete. Jun 6 10:39:07 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 3 of 5 (IP Configure Start) started... Jun 6 10:39:07 lolbox NetworkManager[862]: <info> (eth0): device state change: config -> ip-config (reason 'none') [50 70 0] Jun 6 10:39:07 lolbox NetworkManager[862]: <info> Activation (eth0) Beginning DHCPv4 transaction (timeout in 45 seconds) Jun 6 10:39:07 lolbox NetworkManager[862]: <info> dhclient started with pid 13270 Jun 6 10:39:07 lolbox NetworkManager[862]: <info> Activation (eth0) Beginning DHCPv6 transaction (timeout in 45 seconds) Jun 6 10:39:07 lolbox NetworkManager[862]: <info> dhclient started with pid 13271 Jun 6 10:39:07 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 3 of 5 (IP Configure Start) complete. Jun 6 10:39:07 lolbox avahi-daemon[619]: Withdrawing address record for fe80::6ef0:49ff:feb9:b17f on eth0. Jun 6 10:39:07 lolbox avahi-daemon[619]: Leaving mDNS multicast group on interface eth0.IPv6 with address fe80::6ef0:49ff:feb9:b17f. Jun 6 10:39:07 lolbox avahi-daemon[619]: Interface eth0.IPv6 no longer relevant for mDNS. Jun 6 10:39:07 lolbox dhclient: Internet Systems Consortium DHCP Client 4.2.4 Jun 6 10:39:07 lolbox dhclient: Copyright 2004-2012 Internet Systems Consortium. Jun 6 10:39:07 lolbox dhclient: All rights reserved. Jun 6 10:39:07 lolbox dhclient: For info, please visit https://www.isc.org/software/dhcp/ Jun 6 10:39:07 lolbox dhclient: Jun 6 10:39:08 lolbox dhclient: Internet Systems Consortium DHCP Client 4.2.4 Jun 6 10:39:08 lolbox dhclient: Copyright 2004-2012 Internet Systems Consortium. Jun 6 10:39:08 lolbox dhclient: All rights reserved. Jun 6 10:39:08 lolbox dhclient: For info, please visit https://www.isc.org/software/dhcp/ Jun 6 10:39:08 lolbox dhclient: Jun 6 10:39:08 lolbox dhclient: Bound to *:546 Jun 6 10:39:08 lolbox dhclient: Listening on Socket/eth0 Jun 6 10:39:08 lolbox dhclient: Sending on Socket/eth0 Jun 6 10:39:08 lolbox kernel: [ 1446.098590] type=1400 audit(1402043948.002:75): apparmor="DENIED" operation="signal" profile="/usr/lib/NetworkManager/nm-dhcp-client.action" pid=13273 comm="nm-dhcp-client." requested_mask="send" denied_mask="send" signal=term peer="/sbin/dhclient" Jun 6 10:39:08 lolbox kernel: [ 1446.098599] type=1400 audit(1402043948.002:76): apparmor="DENIED" operation="signal" profile="/sbin/dhclient" pid=13273 comm="nm-dhcp-client." requested_mask="receive" denied_mask="receive" signal=term peer="/usr/lib/NetworkManager/nm-dhcp-client.action" Jun 6 10:39:08 lolbox NetworkManager[862]: <info> (eth0): DHCPv4 state changed nbi -> preinit Jun 6 10:39:08 lolbox dhclient: Listening on LPF/eth0/6c:f0:49:b9:b1:7f Jun 6 10:39:08 lolbox dhclient: Sending on LPF/eth0/6c:f0:49:b9:b1:7f Jun 6 10:39:08 lolbox dhclient: Sending on Socket/fallback Jun 6 10:39:08 lolbox dhclient: DHCPREQUEST of 192.168.0.16 on eth0 to 255.255.255.255 port 67 (xid=0x3e0183b9) Jun 6 10:39:08 lolbox dhclient: XMT: Solicit on eth0, interval 1050ms. Jun 6 10:39:08 lolbox dhclient: send_packet6: Cannot assign requested address Jun 6 10:39:08 lolbox dhclient: dhc6: send_packet6() sent -1 of 77 bytes Jun 6 10:39:09 lolbox dhclient: DHCPACK of 192.168.0.16 from 192.168.0.1 Jun 6 10:39:09 lolbox dhclient: bound to 192.168.0.16 -- renewal in 35498 seconds. Jun 6 10:39:09 lolbox NetworkManager[862]: <info> (eth0): DHCPv4 state changed preinit -> reboot Jun 6 10:39:09 lolbox NetworkManager[862]: <info> address 192.168.0.16 Jun 6 10:39:09 lolbox NetworkManager[862]: <info> prefix 24 (255.255.255.0) Jun 6 10:39:09 lolbox NetworkManager[862]: <info> gateway 192.168.0.1 Jun 6 10:39:09 lolbox NetworkManager[862]: <info> nameserver '83.255.245.11' Jun 6 10:39:09 lolbox NetworkManager[862]: <info> nameserver '193.150.193.150' Jun 6 10:39:09 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 5 of 5 (IPv4 Configure Commit) scheduled... Jun 6 10:39:09 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 5 of 5 (IPv4 Commit) started... Jun 6 10:39:09 lolbox avahi-daemon[619]: Joining mDNS multicast group on interface eth0.IPv4 with address 192.168.0.16. Jun 6 10:39:09 lolbox avahi-daemon[619]: New relevant interface eth0.IPv4 for mDNS. Jun 6 10:39:09 lolbox avahi-daemon[619]: Registering new address record for 192.168.0.16 on eth0.IPv4. Jun 6 10:39:09 lolbox avahi-daemon[619]: Joining mDNS multicast group on interface eth0.IPv6 with address fe80::6ef0:49ff:feb9:b17f. Jun 6 10:39:09 lolbox avahi-daemon[619]: New relevant interface eth0.IPv6 for mDNS. Jun 6 10:39:09 lolbox avahi-daemon[619]: Registering new address record for fe80::6ef0:49ff:feb9:b17f on eth0.*. Jun 6 10:39:10 lolbox dhclient: XMT: Solicit on eth0, interval 2180ms. Jun 6 10:39:10 lolbox dhclient: RCV: Advertise message on eth0 from fe80::120d:7fff:fe97:9d54. Jun 6 10:39:10 lolbox dhclient: IA_NA status code NoAddrsAvail. Jun 6 10:39:10 lolbox NetworkManager[862]: <info> (eth0): device state change: ip-config -> secondaries (reason 'none') [70 90 0] Jun 6 10:39:10 lolbox NetworkManager[862]: <info> Activation (eth0) Stage 5 of 5 (IPv4 Commit) complete. Jun 6 10:39:10 lolbox NetworkManager[862]: <info> (eth0): device state change: secondaries -> activated (reason 'none') [90 100 0] Jun 6 10:39:10 lolbox NetworkManager[862]: <info> NetworkManager state is now CONNECTED_GLOBAL Jun 6 10:39:10 lolbox NetworkManager[862]: <info> Policy set 'Wired connection 1' (eth0) as default for IPv4 routing and DNS. Jun 6 10:39:10 lolbox NetworkManager[862]: <info> Writing DNS information to /sbin/resolvconf Jun 6 10:39:10 lolbox dnsmasq[1362]: setting upstream servers from DBus Jun 6 10:39:10 lolbox dnsmasq[1362]: using nameserver 127.0.0.1#53 Jun 6 10:39:10 lolbox dnsmasq[1362]: using nameserver 193.150.193.150#53 Jun 6 10:39:10 lolbox dnsmasq[1362]: using nameserver 83.255.245.11#53 Jun 6 10:39:10 lolbox NetworkManager[862]: <info> Activation (eth0) successful, device activated. Jun 6 10:39:10 lolbox whoopsie[1133]: message repeated 2 times: [ offline] Jun 6 10:39:10 lolbox whoopsie[1133]: online Jun 6 10:39:10 lolbox ntpdate[13339]: Can't find host ntp.ubuntu.com: Name or service not known (-2) Jun 6 10:39:10 lolbox ntpdate[13339]: no servers can be used, exiting Jun 6 10:39:11 lolbox dnsmasq[1138]: reading /var/run/dnsmasq/resolv.conf Jun 6 10:39:11 lolbox dnsmasq[1138]: using nameserver 127.0.1.1#53 Jun 6 10:39:12 lolbox dhclient: XMT: Solicit on eth0, interval 4350ms. Jun 6 10:39:12 lolbox dhclient: RCV: Advertise message on eth0 from fe80::120d:7fff:fe97:9d54. Jun 6 10:39:12 lolbox dhclient: IA_NA status code NoAddrsAvail. Jun 6 10:39:16 lolbox dhclient: XMT: Solicit on eth0, interval 8740ms. Jun 6 10:39:16 lolbox dhclient: RCV: Advertise message on eth0 from fe80::120d:7fff:fe97:9d54. Jun 6 10:39:16 lolbox dhclient: IA_NA status code NoAddrsAvail. Jun 6 10:39:17 lolbox dnsmasq[1138]: Maximum number of concurrent DNS queries reached (max: 150) Jun 6 10:39:17 lolbox dnsmasq[1362]: Maximum number of concurrent DNS queries reached (max: 150) Jun 6 10:39:25 lolbox dhclient: XMT: Solicit on eth0, interval 17610ms. Jun 6 10:39:25 lolbox dhclient: RCV: Advertise message on eth0 from fe80::120d:7fff:fe97:9d54. Jun 6 10:39:25 lolbox dhclient: IA_NA status code NoAddrsAvail.

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Using Razor together with ASP.NET Web API

- by Fredrik N

On the blog post “If Then, If Then, If Then, MVC” I found the following code example: [HttpGet]public ActionResult List() { var list = new[] { "John", "Pete", "Ben" }; if (Request.AcceptTypes.Contains("application/json")) { return Json(list, JsonRequestBehavior.AllowGet); } if (Request.IsAjaxRequest()) [ return PartialView("_List", list); } return View(list); } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } The code is a ASP.NET MVC Controller where it reuse the same “business” code but returns JSON if the request require JSON, a partial view when the request is an AJAX request or a normal ASP.NET MVC View. The above code may have several reasons to be changed, and also do several things, the code is not closed for modifications. To extend the code with a new way of presenting the model, the code need to be modified. So I started to think about how the above code could be rewritten so it will follow the Single Responsibility and open-close principle. I came up with the following result and with the use of ASP.NET Web API: public String[] Get() { return new[] { "John", "Pete", "Ben" }; } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } It just returns the model, nothing more. The code will do one thing and it will do it well. But it will not solve the problem when it comes to return Views. If we use the ASP.NET Web Api we can get the result as JSON or XML, but not as a partial view or as a ASP.NET MVC view. Wouldn’t it be nice if we could do the following against the Get() method? Accept: application/json JSON will be returned – Already part of the Web API Accept: text/html Returns the model as HTML by using a View The best thing, it’s possible! By using the RazorEngine I created a custom MediaTypeFormatter (RazorFormatter, code at the end of this blog post) and associate it with the media type “text/html”. I decided to use convention before configuration to decide which Razor view should be used to render the model. To register the formatter I added the following code to Global.asax: GlobalConfiguration.Configuration.Formatters.Add(new RazorFormatter()); Here is an example of a ApiController that just simply returns a model: using System.Web.Http; namespace WebApiRazor.Controllers { public class CustomersController : ApiController { // GET api/values public Customer Get() { return new Customer { Name = "John Doe", Country = "Sweden" }; } } public class Customer { public string Name { get; set; } public string Country { get; set; } } } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } Because I decided to use convention before configuration I only need to add a view with the same name as the model, Customer.cshtml, here is the example of the View: <!DOCTYPE html> <html> <head> <script src="http://ajax.aspnetcdn.com/ajax/jquery/jquery-1.5.1.min.js" type="text/javascript"></script> </head> <body> <div id="body"> <section> <div> <hgroup> <h1>Welcome '@Model.Name' to ASP.NET Web API Razor Formatter!</h1> </hgroup> </div> <p> Using the same URL "api/values" but using AJAX: <button>Press to show content!</button> </p> <p> </p> </section> </div> </body> <script type="text/javascript"> $("button").click(function () { $.ajax({ url: '/api/values', type: "GET", contentType: "application/json; charset=utf-8", success: function(data, status, xhr) { alert(data.Name); }, error: function(xhr, status, error) { alert(error); }}); }); </script> </html> .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } Now when I open up a browser and enter the following URL: http://localhost/api/customers the above View will be displayed and it will render the model the ApiController returns. If I use Ajax against the same ApiController with the content type set to “json”, the ApiController will now return the model as JSON. Here is a part of a really early prototype of the Razor formatter (The code is far from perfect, just use it for testing). I will rewrite the code and also make it possible to specify an attribute to the returned model, so it can decide which view to be used when the media type is “text/html”, but by default the formatter will use convention: using System; using System.Net.Http.Formatting; namespace WebApiRazor.Models { using System.IO; using System.Net; using System.Net.Http.Headers; using System.Reflection; using System.Threading.Tasks; using RazorEngine; public class RazorFormatter : MediaTypeFormatter { public RazorFormatter() { SupportedMediaTypes.Add(new MediaTypeHeaderValue("text/html")); SupportedMediaTypes.Add(new MediaTypeHeaderValue("application/xhtml+xml")); } //... public override Task WriteToStreamAsync( Type type, object value, Stream stream, HttpContentHeaders contentHeaders, TransportContext transportContext) { var task = Task.Factory.StartNew(() => { var viewPath = // Get path to the view by the name of the type var template = File.ReadAllText(viewPath); Razor.Compile(template, type, type.Name); var razor = Razor.Run(type.Name, value); var buf = System.Text.Encoding.Default.GetBytes(razor); stream.Write(buf, 0, buf.Length); stream.Flush(); }); return task; } } } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } Summary By using formatters and the ASP.NET Web API we can easily just extend our code without doing any changes to our ApiControllers when we want to return a new format. This blog post just showed how we can extend the Web API to use Razor to format a returned model into HTML. If you want to know when I will post more blog posts, please feel free to follow me on twitter: @fredrikn

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Creating a JSONP Formatter for ASP.NET Web API

- by Rick Strahl

Out of the box ASP.NET WebAPI does not include a JSONP formatter, but it's actually very easy to create a custom formatter that implements this functionality. JSONP is one way to allow Browser based JavaScript client applications to bypass cross-site scripting limitations and serve data from the non-current Web server. AJAX in Web Applications uses the XmlHttp object which by default doesn't allow access to remote domains. There are number of ways around this limitation <script> tag loading and JSONP is one of the easiest and semi-official ways that you can do this. JSONP works by combining JSON data and wrapping it into a function call that is executed when the JSONP data is returned. If you use a tool like jQUery it's extremely easy to access JSONP content. Imagine that you have a URL like this: http://RemoteDomain/aspnetWebApi/albums which on an HTTP GET serves some data - in this case an array of record albums. This URL is always directly accessible from an AJAX request if the URL is on the same domain as the parent request. However, if that URL lives on a separate server it won't be easily accessible to an AJAX request. Now, if the server can serve up JSONP this data can be accessed cross domain from a browser client. Using jQuery it's really easy to retrieve the same data with JSONP:function getAlbums() { $.getJSON("http://remotedomain/aspnetWebApi/albums?callback=?",null, function (albums) { alert(albums.length); }); } The resulting callback the same as if the call was to a local server when the data is returned. jQuery deserializes the data and feeds it into the method. Here the array is received and I simply echo back the number of items returned. From here your app is ready to use the data as needed. This all works fine - as long as the server can serve the data with JSONP. What does JSONP look like? JSONP is a pretty simple 'protocol'. All it does is wrap a JSON response with a JavaScript function call. The above result from the JSONP call looks like this:Query17103401925975181569_1333408916499( [{"Id":"34043957","AlbumName":"Dirty Deeds Done Dirt Cheap",…},{…}] ) The way JSONP works is that the client (jQuery in this case) sends of the request, receives the response and evals it. The eval basically executes the function and deserializes the JSON inside of the function. It's actually a little more complex for the framework that does this, but that's the gist of what happens. JSONP works by executing the code that gets returned from the JSONP call. JSONP and ASP.NET Web API As mentioned previously, JSONP support is not natively in the box with ASP.NET Web API. But it's pretty easy to create and plug-in a custom formatter that provides this functionality. The following code is based on Christian Weyers example but has been updated to the latest Web API CodePlex bits, which changes the implementation a bit due to the way dependent objects are exposed differently in the latest builds. Here's the code: using System; using System.IO; using System.Net; using System.Net.Http.Formatting; using System.Net.Http.Headers; using System.Threading.Tasks; using System.Web; using System.Net.Http; namespace Westwind.Web.WebApi { /// <summary> /// Handles JsonP requests when requests are fired with /// text/javascript or application/json and contain /// a callback= (configurable) query string parameter /// /// Based on Christian Weyers implementation /// https://github.com/thinktecture/Thinktecture.Web.Http/blob/master/Thinktecture.Web.Http/Formatters/JsonpFormatter.cs /// </summary> public class JsonpFormatter : JsonMediaTypeFormatter { public JsonpFormatter() { SupportedMediaTypes.Add(new MediaTypeHeaderValue("application/json")); SupportedMediaTypes.Add(new MediaTypeHeaderValue("text/javascript")); //MediaTypeMappings.Add(new UriPathExtensionMapping("jsonp", "application/json")); JsonpParameterName = "callback"; } /// <summary> /// Name of the query string parameter to look for /// the jsonp function name /// </summary> public string JsonpParameterName {get; set; } /// <summary> /// Captured name of the Jsonp function that the JSON call /// is wrapped in. Set in GetPerRequestFormatter Instance /// </summary> private string JsonpCallbackFunction; public override bool CanWriteType(Type type) { return true; } /// <summary> /// Override this method to capture the Request object /// and look for the query string parameter and /// create a new instance of this formatter. /// /// This is the only place in a formatter where the /// Request object is available. /// </summary> /// <param name="type"></param> /// <param name="request"></param> /// <param name="mediaType"></param> /// <returns></returns> public override MediaTypeFormatter GetPerRequestFormatterInstance(Type type, HttpRequestMessage request, MediaTypeHeaderValue mediaType) { var formatter = new JsonpFormatter() { JsonpCallbackFunction = GetJsonCallbackFunction(request) }; return formatter; } /// <summary> /// Override to wrap existing JSON result with the /// JSONP function call /// </summary> /// <param name="type"></param> /// <param name="value"></param> /// <param name="stream"></param> /// <param name="contentHeaders"></param> /// <param name="transportContext"></param> /// <returns></returns> public override Task WriteToStreamAsync(Type type, object value, Stream stream, HttpContentHeaders contentHeaders, TransportContext transportContext) { if (!string.IsNullOrEmpty(JsonpCallbackFunction)) { return Task.Factory.StartNew(() => { var writer = new StreamWriter(stream); writer.Write( JsonpCallbackFunction + "("); writer.Flush(); base.WriteToStreamAsync(type, value, stream, contentHeaders, transportContext).Wait(); writer.Write(")"); writer.Flush(); }); } else { return base.WriteToStreamAsync(type, value, stream, contentHeaders, transportContext); } } /// <summary> /// Retrieves the Jsonp Callback function /// from the query string /// </summary> /// <returns></returns> private string GetJsonCallbackFunction(HttpRequestMessage request) { if (request.Method != HttpMethod.Get) return null; var query = HttpUtility.ParseQueryString(request.RequestUri.Query); var queryVal = query[this.JsonpParameterName]; if (string.IsNullOrEmpty(queryVal)) return null; return queryVal; } } } Note again that this code will not work with the Beta bits of Web API - it works only with post beta bits from CodePlex and hopefully this will continue to work until RTM :-) This code is a bit different from Christians original code as the API has changed. The biggest change is that the Read/Write functions no longer receive a global context object that gives access to the Request and Response objects as the older bits did. Instead you now have to override the GetPerRequestFormatterInstance() method, which receives the Request as a parameter. You can capture the Request there, or use the request to pick up the values you need and store them on the formatter. Note that I also have to create a new instance of the formatter since I'm storing request specific state on the instance (information whether the callback= querystring is present) so I return a new instance of this formatter. Other than that the code should be straight forward: The code basically writes out the function pre- and post-amble and the defers to the base stream to retrieve the JSON to wrap the function call into. The code uses the Async APIs to write this data out (this will take some getting used to seeing all over the place for me). Hooking up the JsonpFormatter Once you've created a formatter, it has to be added to the request processing sequence by adding it to the formatter collection. Web API is configured via the static GlobalConfiguration object. protected void Application_Start(object sender, EventArgs e) { // Verb Routing RouteTable.Routes.MapHttpRoute( name: "AlbumsVerbs", routeTemplate: "albums/{title}", defaults: new { title = RouteParameter.Optional, controller = "AlbumApi" } ); GlobalConfiguration .Configuration .Formatters .Insert(0, new Westwind.Web.WebApi.JsonpFormatter()); } That's all it takes. Note that I added the formatter at the top of the list of formatters, rather than adding it to the end which is required. The JSONP formatter needs to fire before any other JSON formatter since it relies on the JSON formatter to encode the actual JSON data. If you reverse the order the JSONP output never shows up. So, in general when adding new formatters also try to be aware of the order of the formatters as they are added. Resources JsonpFormatter Code on GitHub© Rick Strahl, West Wind Technologies, 2005-2012Posted in Web Api Tweet !function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0];if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src="//platform.twitter.com/widgets.js";fjs.parentNode.insertBefore(js,fjs);}}(document,"script","twitter-wjs"); (function() { var po = document.createElement('script'); po.type = 'text/javascript'; po.async = true; po.src = 'https://apis.google.com/js/plusone.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(po, s); })();

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C#: Adding Functionality to 3rd Party Libraries With Extension Methods

- by James Michael Hare

Ever have one of those third party libraries that you love but it's missing that one feature or one piece of syntactical candy that would make it so much more useful? This, I truly think, is one of the best uses of extension methods. I began discussing extension methods in my last post (which you find here) where I expounded upon what I thought were some rules of thumb for using extension methods correctly. As long as you keep in line with those (or similar) rules, they can often be useful for adding that little extra functionality or syntactical simplification for a library that you have little or no control over. Oh sure, you could take an open source project, download the source and add the methods you want, but then every time the library is updated you have to re-add your changes, which can be cumbersome and error prone. And yes, you could possibly extend a class in a third party library and override features, but that's only if the class is not sealed, static, or constructed via factories. This is the perfect place to use an extension method! And the best part is, you and your development team don't need to change anything! Simply add the using for the namespace the extensions are in! So let's consider this example. I love log4net! Of all the logging libraries I've played with, it, to me, is one of the most flexible and configurable logging libraries and it performs great. But this isn't about log4net, well, not directly. So why would I want to add functionality? Well, it's missing one thing I really want in the ILog interface: ability to specify logging level at runtime. For example, let's say I declare my ILog instance like so: using log4net; public class LoggingTest { private static readonly ILog _log = LogManager.GetLogger(typeof(LoggingTest)); ... } If you don't know log4net, the details aren't important, just to show that the field _log is the logger I have gotten from log4net. So now that I have that, I can log to it like so: _log.Debug("This is the lowest level of logging and just for debugging output."); _log.Info("This is an informational message. Usual normal operation events."); _log.Warn("This is a warning, something suspect but not necessarily wrong."); _log.Error("This is an error, some sort of processing problem has happened."); _log.Fatal("Fatals usually indicate the program is dying hideously."); And there's many flavors of each of these to log using string formatting, to log exceptions, etc. But one thing there isn't: the ability to easily choose the logging level at runtime. Notice, the logging levels above are chosen at compile time. Of course, you could do some fun stuff with lambdas and wrap it, but that would obscure the simplicity of the interface. And yes there is a Logger property you can dive down into where you can specify a Level, but the Level properties don't really match the ILog interface exactly and then you have to manually build a LogEvent and... well, it gets messy. I want something simple and sexy so I can say: _log.Log(someLevel, "This will be logged at whatever level I choose at runtime!"); Now, some purists out there might say you should always know what level you want to log at, and for the most part I agree with them. For the most party the ILog interface satisfies 99% of my needs. In fact, for most application logging yes you do always know the level you will be logging at, but when writing a utility class, you may not always know what level your user wants. I'll tell you, one of my favorite things is to write reusable components. If I had my druthers I'd write framework libraries and shared components all day! And being able to easily log at a runtime-chosen level is a big need for me. After all, if I want my code to really be re-usable, I shouldn't force a user to deal with the logging level I choose. One of my favorite uses for this is in Interceptors -- I'll describe Interceptors in my next post and some of my favorites -- for now just know that an Interceptor wraps a class and allows you to add functionality to an existing method without changing it's signature. At the risk of over-simplifying, it's a very generic implementation of the Decorator design pattern. So, say for example that you were writing an Interceptor that would time method calls and emit a log message if the method call execution time took beyond a certain threshold of time. For instance, maybe if your database calls take more than 5,000 ms, you want to log a warning. Or if a web method call takes over 1,000 ms, you want to log an informational message. This would be an excellent use of logging at a generic level. So here was my personal wish-list of requirements for my task: Be able to determine if a runtime-specified logging level is enabled. Be able to log generically at a runtime-specified logging level. Have the same look-and-feel of the existing Debug, Info, Warn, Error, and Fatal calls. Having the ability to also determine if logging for a level is on at runtime is also important so you don't spend time building a potentially expensive logging message if that level is off. Consider an Interceptor that may log parameters on entrance to the method. If you choose to log those parameter at DEBUG level and if DEBUG is not on, you don't want to spend the time serializing those parameters. Now, mine may not be the most elegant solution, but it performs really well since the enum I provide all uses contiguous values -- while it's never guaranteed, contiguous switch values usually get compiled into a jump table in IL which is VERY performant - O(1) - but even if it doesn't, it's still so fast you'd never need to worry about it. So first, I need a way to let users pass in logging levels. Sure, log4net has a Level class, but it's a class with static members and plus it provides way too many options compared to ILog interface itself -- and wouldn't perform as well in my level-check -- so I define an enum like below. namespace Shared.Logging.Extensions { // enum to specify available logging levels. public enum LoggingLevel { Debug, Informational, Warning, Error, Fatal } } Now, once I have this, writing the extension methods I need is trivial. Once again, I would typically /// comment fully, but I'm eliminating for blogging brevity: namespace Shared.Logging.Extensions { // the extension methods to add functionality to the ILog interface public static class LogExtensions { // Determines if logging is enabled at a given level. public static bool IsLogEnabled(this ILog logger, LoggingLevel level) { switch (level) { case LoggingLevel.Debug: return logger.IsDebugEnabled; case LoggingLevel.Informational: return logger.IsInfoEnabled; case LoggingLevel.Warning: return logger.IsWarnEnabled; case LoggingLevel.Error: return logger.IsErrorEnabled; case LoggingLevel.Fatal: return logger.IsFatalEnabled; } return false; } // Logs a simple message - uses same signature except adds LoggingLevel public static void Log(this ILog logger, LoggingLevel level, object message) { switch (level) { case LoggingLevel.Debug: logger.Debug(message); break; case LoggingLevel.Informational: logger.Info(message); break; case LoggingLevel.Warning: logger.Warn(message); break; case LoggingLevel.Error: logger.Error(message); break; case LoggingLevel.Fatal: logger.Fatal(message); break; } } // Logs a message and exception to the log at specified level. public static void Log(this ILog logger, LoggingLevel level, object message, Exception exception) { switch (level) { case LoggingLevel.Debug: logger.Debug(message, exception); break; case LoggingLevel.Informational: logger.Info(message, exception); break; case LoggingLevel.Warning: logger.Warn(message, exception); break; case LoggingLevel.Error: logger.Error(message, exception); break; case LoggingLevel.Fatal: logger.Fatal(message, exception); break; } } // Logs a formatted message to the log at the specified level. public static void LogFormat(this ILog logger, LoggingLevel level, string format, params object[] args) { switch (level) { case LoggingLevel.Debug: logger.DebugFormat(format, args); break; case LoggingLevel.Informational: logger.InfoFormat(format, args); break; case LoggingLevel.Warning: logger.WarnFormat(format, args); break; case LoggingLevel.Error: logger.ErrorFormat(format, args); break; case LoggingLevel.Fatal: logger.FatalFormat(format, args); break; } } } } So there it is! I didn't have to modify the log4net source code, so if a new version comes out, i can just add the new assembly with no changes. I didn't have to subclass and worry about developers not calling my sub-class instead of the original. I simply provide the extension methods and it's as if the long lost extension methods were always a part of the ILog interface! Consider a very contrived example using the original interface: // using the original ILog interface public class DatabaseUtility { private static readonly ILog _log = LogManager.Create(typeof(DatabaseUtility)); // some theoretical method to time IDataReader Execute(string statement) { var timer = new System.Diagnostics.Stopwatch(); // do DB magic // this is hard-coded to warn, if want to change at runtime tough luck! if (timer.ElapsedMilliseconds > 5000 && _log.IsWarnEnabled) { _log.WarnFormat("Statement {0} took too long to execute.", statement); } ... } } Now consider this alternate call where the logging level could be perhaps a property of the class // using the original ILog interface public class DatabaseUtility { private static readonly ILog _log = LogManager.Create(typeof(DatabaseUtility)); // allow logging level to be specified by user of class instead public LoggingLevel ThresholdLogLevel { get; set; } // some theoretical method to time IDataReader Execute(string statement) { var timer = new System.Diagnostics.Stopwatch(); // do DB magic // this is hard-coded to warn, if want to change at runtime tough luck! if (timer.ElapsedMilliseconds > 5000 && _log.IsLogEnabled(ThresholdLogLevel)) { _log.LogFormat(ThresholdLogLevel, "Statement {0} took too long to execute.", statement); } ... } } Next time, I'll show one of my favorite uses for these extension methods in an Interceptor.

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C#: String Concatenation vs Format vs StringBuilder

- by James Michael Hare

I was looking through my groups’ C# coding standards the other day and there were a couple of legacy items in there that caught my eye. They had been passed down from committee to committee so many times that no one even thought to second guess and try them for a long time. It’s yet another example of how micro-optimizations can often get the best of us and cause us to write code that is not as maintainable as it could be for the sake of squeezing an extra ounce of performance out of our software. So the two standards in question were these, in paraphrase: Prefer StringBuilder or string.Format() to string concatenation. Prefer string.Equals() with case-insensitive option to string.ToUpper().Equals(). Now some of you may already know what my results are going to show, as these items have been compared before on many blogs, but I think it’s always worth repeating and trying these yourself. So let’s dig in. The first test was a pretty standard one. When concattenating strings, what is the best choice: StringBuilder, string concattenation, or string.Format()? So before we being I read in a number of iterations from the console and a length of each string to generate. Then I generate that many random strings of the given length and an array to hold the results. Why am I so keen to keep the results? Because I want to be able to snapshot the memory and don’t want garbage collection to collect the strings, hence the array to keep hold of them. I also didn’t want the random strings to be part of the allocation, so I pre-allocate them and the array up front before the snapshot. So in the code snippets below: num – Number of iterations. strings – Array of randomly generated strings. results – Array to hold the results of the concatenation tests. timer – A System.Diagnostics.Stopwatch() instance to time code execution. start – Beginning memory size. stop – Ending memory size. after – Memory size after final GC. So first, let’s look at the concatenation loop: 1: // build num strings using concattenation. 2: for (int i = 0; i < num; i++) 3: { 4: results[i] = "This is test #" + i + " with a result of " + strings[i]; 5: } Pretty standard, right? Next for string.Format(): 1: // build strings using string.Format() 2: for (int i = 0; i < num; i++) 3: { 4: results[i] = string.Format("This is test #{0} with a result of {1}", i, strings[i]); 5: } Finally, StringBuilder: 1: // build strings using StringBuilder 2: for (int i = 0; i < num; i++) 3: { 4: var builder = new StringBuilder(); 5: builder.Append("This is test #"); 6: builder.Append(i); 7: builder.Append(" with a result of "); 8: builder.Append(strings[i]); 9: results[i] = builder.ToString(); 10: } So I take each of these loops, and time them by using a block like this: 1: // get the total amount of memory used, true tells it to run GC first. 2: start = System.GC.GetTotalMemory(true); 3: 4: // restart the timer 5: timer.Reset(); 6: timer.Start(); 7: 8: // *** code to time and measure goes here. *** 9: 10: // get the current amount of memory, stop the timer, then get memory after GC. 11: stop = System.GC.GetTotalMemory(false); 12: timer.Stop(); 13: other = System.GC.GetTotalMemory(true); So let’s look at what happens when I run each of these blocks through the timer and memory check at 500,000 iterations: 1: Operator + - Time: 547, Memory: 56104540/55595960 - 500000 2: string.Format() - Time: 749, Memory: 57295812/55595960 - 500000 3: StringBuilder - Time: 608, Memory: 55312888/55595960 – 500000 Egad! string.Format brings up the rear and + triumphs, well, at least in terms of speed. The concat burns more memory than StringBuilder but less than string.Format(). This shows two main things: StringBuilder is not always the panacea many think it is. The difference between any of the three is miniscule! The second point is extremely important! You will often here people who will grasp at results and say, “look, operator + is 10% faster than StringBuilder so always use StringBuilder.” Statements like this are a disservice and often misleading. For example, if I had a good guess at what the size of the string would be, I could have preallocated my StringBuffer like so: 1: for (int i = 0; i < num; i++) 2: { 3: // pre-declare StringBuilder to have 100 char buffer. 4: var builder = new StringBuilder(100); 5: builder.Append("This is test #"); 6: builder.Append(i); 7: builder.Append(" with a result of "); 8: builder.Append(strings[i]); 9: results[i] = builder.ToString(); 10: } Now let’s look at the times: 1: Operator + - Time: 551, Memory: 56104412/55595960 - 500000 2: string.Format() - Time: 753, Memory: 57296484/55595960 - 500000 3: StringBuilder - Time: 525, Memory: 59779156/55595960 - 500000 Whoa! All of the sudden StringBuilder is back on top again! But notice, it takes more memory now. This makes perfect sense if you examine the IL behind the scenes. Whenever you do a string concat (+) in your code, it examines the lengths of the arguments and creates a StringBuilder behind the scenes of the appropriate size for you. But even IF we know the approximate size of our StringBuilder, look how much less readable it is! That’s why I feel you should always take into account both readability and performance. After all, consider all these timings are over 500,000 iterations. That’s at best 0.0004 ms difference per call which is neglidgable at best. The key is to pick the best tool for the job. What do I mean? Consider these awesome words of wisdom: Concatenate (+) is best at concatenating. StringBuilder is best when you need to building. Format is best at formatting. Totally Earth-shattering, right! But if you consider it carefully, it actually has a lot of beauty in it’s simplicity. Remember, there is no magic bullet. If one of these always beat the others we’d only have one and not three choices. The fact is, the concattenation operator (+) has been optimized for speed and looks the cleanest for joining together a known set of strings in the simplest manner possible. StringBuilder, on the other hand, excels when you need to build a string of inderterminant length. Use it in those times when you are looping till you hit a stop condition and building a result and it won’t steer you wrong. String.Format seems to be the looser from the stats, but consider which of these is more readable. Yes, ignore the fact that you could do this with ToString() on a DateTime. 1: // build a date via concatenation 2: var date1 = (month < 10 ? string.Empty : "0") + month + '/' 3: + (day < 10 ? string.Empty : "0") + '/' + year; 4: 5: // build a date via string builder 6: var builder = new StringBuilder(10); 7: if (month < 10) builder.Append('0'); 8: builder.Append(month); 9: builder.Append('/'); 10: if (day < 10) builder.Append('0'); 11: builder.Append(day); 12: builder.Append('/'); 13: builder.Append(year); 14: var date2 = builder.ToString(); 15: 16: // build a date via string.Format 17: var date3 = string.Format("{0:00}/{1:00}/{2:0000}", month, day, year); 18: So the strength in string.Format is that it makes constructing a formatted string easy to read. Yes, it’s slower, but look at how much more elegant it is to do zero-padding and anything else string.Format does. So my lesson is, don’t look for the silver bullet! Choose the best tool. Micro-optimization almost always bites you in the end because you’re sacrificing readability for performance, which is almost exactly the wrong choice 90% of the time. I love the rules of optimization. They’ve been stated before in many forms, but here’s how I always remember them: For Beginners: Do not optimize. For Experts: Do not optimize yet. It’s so true. Most of the time on today’s modern hardware, a micro-second optimization at the sake of readability will net you nothing because it won’t be your bottleneck. Code for readability, choose the best tool for the job which will usually be the most readable and maintainable as well. Then, and only then, if you need that extra performance boost after profiling your code and exhausting all other options… then you can start to think about optimizing.

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CodePlex Daily Summary for Wednesday, October 03, 2012

CodePlex Daily Summary for Wednesday, October 03, 2012Popular ReleasesSharePoint Column & View Permission: SharePoint Column and View Permission v1.5: Version 1.5 of this project. If you will find any bugs please let me know at enti@zoznam.sk or post your findings in Issue TrackerZ3: Z3 4.1.1 source code: Snapshot corresponding to version 4.1.1.DirectX Tool Kit: October 2012: October 2, 2012 Added ScreenGrab module Added CreateGeoSphere for drawing a geodesic sphere Put DDSTextureLoader and WICTextureLoader into the DirectX C++ namespace Renamed project files for better naming consistency Updated WICTextureLoader for Windows 8 96bpp floating-point formats Win32 desktop projects updated to use Windows Vista (0x0600) rather than Windows 7 (0x0601) APIs Tweaked SpriteBatch.cpp to workaround ARM NEON compiler codegen bugHome Access Plus+: v8.1: HAP+ Web v8.1.1003.000079318 Fixed: Issue with the Help Desk and updating a ticket as an admin 79319 Fixed: formatting issue with the booking system admin header 79321 Moved to using the arrow with a circle symbol on the homepage instead of the > and < 79541 Added: 480px wide mobile theme to login page 79541 Added: 480px wide mobile theme to home page 79541 Added: slide events for homepage 79553 Fixed: Booking System Multiple Lesson Bug 79553 Fixed: IE Error Message 79684 Fixed: jQuery issue ...System.Net.FtpClient: System.Net.FtpClient 2012.10.02: This is the first release of the new code base. It is not compatible with the old API, I repeat it is not a drop in update for projects currently using System.Net.FtpClient. New users should download this release. The old code base (Branch: System.Net.FtpClient_1) will continue to be supported while the new code matures. This release is a complete re-write of System.Net.FtpClient. The API and code are simpler than ever before. There are some new features included as well as an attempt at be...CRM 2011 Visual Ribbon Editor: Visual Ribbon Editor (1.3.1002.3): Visual Ribbon Editor 1.3.1002.3 What's New: Multi-language support for Labels/Tooltips for custom buttons and groups Support for base language other than English (1033) Connect dialog will not require organization name for ADFS / IFD connections Automatic creation of missing labels for all provisioned languages Minor connection issues fixed Notes: Before saving the ribbon to CRM server, editor will check Ribbon XML for any missing <Title> elements inside existing <LocLabel> elements...YAXLib: Yet Another XML Serialization Library for the .NET Framework: YAXLib 2.10: See change-log for the list of new features added and bugs fixedRenameApp: RenameApp 1.0: First release of RenameAppJsonToStaticTypeGenerator: JsonToStaticTypeGenerator 0.1: This is the first alpha release of JsonToStaticTypeGenerator.XiaoKyun: XiaoKyun V1.00: https://xiaokyun.codeplex.com/CatchThatException: Release 1.12: Wow a very fast change and a much better and faster writing to the text fileNaked Objects: Naked Objects Release 5.0.0: Corresponds to the packaged version 5.0.0 available via NuGet. Please note that the easiest way to install and run the Naked Objects Framework is via the NuGet package manager: just search the Official NuGet Package Source for 'nakedobjects'. It is only necessary to download the source code (from here) if you wish to modify or re-build the framework yourself. If you do wish to re-build the framework, consul the file HowToBuild.txt in the release. Major enhancementsNaked Objects 5.0 is desi...WinRT XAML Toolkit: WinRT XAML Toolkit - 1.3.0: WinRT XAML Toolkit based on the Windows 8 RTM SDK. Download the latest source from the SOURCE CODE page. For compiled version use NuGet. You can add it to your project in Visual Studio by going to View/Other Windows/Package Manager Console and entering: PM> Install-Package winrtxamltoolkit Features AsyncUI extensions Controls and control extensions Converters Debugging helpers Imaging IO helpers VisualTree helpers Samples Recent changes NOTE: Namespace changes DebugConsol...D3 Loot Tracker: 1.4.1: This version will automatically save a recording session on application exit if the user didn't stop the current session.SubExtractor: Release 1029: Feature: Added option to make i and ¡ characters movie-specific for improved OCR on Spanish subs (Special Characters tab in Options) Feature: Allow switch to Word Spacing dialog directly from Spell Check dialog Fix: Added more default word spacings for accented characters Fix: Changed Word Spacing dialog to show all OCR'd characters in current sub Fix: Removed application focus grab during OCR Fix: Tightened HD subs fuzzy logic to reduce false matches in small characters Fix: Improved Arrow k...MCEBuddy 2.x: MCEBuddy 2.2.18: Reccomended download Changelog for 2.2.18 (32bit and 64bit) 1. Added support for checking if Showanalyzer has hung and cancelling it 2. New version of comskip, 0.81.48 3. Speeding up comskip 4. Fixed a build bug in 64bit 2.2.17 5. Added a new comkip.ini, better commercial detection for international channels and less aggressive. Old one has been retained as comskip_old.ini 6. Added support for Audio Offset on Conversion Task page in GUI (this overrides the profiles AudioDelay when specified)Readable Passphrase Generator: KeePass Plugin 0.7.1: See the KeePass Plugin Step By Step Guide for instructions on how to install the plugin. Changes Built against KeePass 2.20Windows 8 Toolkit - Charts and More: Beta 1.0: The First Compiled Version of my LibraryPDF.NET: PDF.NET.Ver4.5-OpenSourceCode: PDF.NET Ver4.5 ????，????Web??????。 PDF.NET Ver4.5 Open Source Code,include a sample Web application project.Visual Studio Icon Patcher: Version 1.5.2: This version contains no new images from v1.5.1 Contains the following improvements: Better support for detecting the installed languages The extract & inject commands won’t run if Visual Studio is running You may now run in extract or inject mode The p/invoke code was cleaned up based on Code Analysis recommendations When a p/invoke method fails the Win32 error message is now displayed Error messages use red text Status messages use green textNew Projects.Net Exception Reporter: A reusable and extensible exception reporter for Microsoft .NET projects.Aesha Broker: A rich client Auction House Broker application. Built upon Blizzard's new REST API. Provides a client experience which caches historical auction data to provideASP.NET Friendly URLs: A library that enables automatic resolving of extensionless URLs to ASP.NET file-based handlers, e.g. ASPX pages.Astro Power CMS: Astro Power CMS build on GraffitiCMS, a product of Telligent. GraffitiCMS stop develop, I create this project with name is Astro Power CMSaTester: Here is a good place. And now, I can upload my soruce to it. It's very good.Automacao Residencial: O Netduino é uma plataforma onde voce utiliza a linguagem C# para controlar hardware. O objetivo é criar uma estrutura de comunicaçao com o netduino.Derbster: Explore and learn about modern C# architecture and programming by implementing software to support the modern game of roller derby. Dot FPE - A free Format-preserving encryption implementation for .net: There aren't any widely available implementations of a format-preserving encryption in .NET. Thus we aim to be the first!DotNetEx: .NET Framework extended functionality for data access, working with Tasks and asynchronous programming, encryption algorithms such as SkipJack and other stuff.Elemental Development Toolchain (.NET version): A complete toolchain built around the Æthere langauge.elFinder ASP.NET Connector: The one and only .NET connector for the amazing elFinder 2.X web-based file manager. Finally you can manage your files easily right from your browser!Geosynkronisering: Prosjekt for utarbeidelse av spesifikasjoner for grensesnitt som muliggjør synkronisering av datalager med geografisk datainnhold på tvers av ulike plattformerGIII_P1: Jesli wszyscy w Ciebie zwatpili pokaz ze sie mylili !IntroduceCompany: Website gi?i thi?u doanh nghi?p - công ty.JsonToStaticTypeGenerator: This is the JsonToStaticTypeGenerator project that gives the possibility to generate c# classes out of Json data.kwerty: Coming soonMachine Learning: My machine learning project. Just to figure out things...MicroManager: MaNGOS Web-based ManagerMvcContrib3: This is the version of mvccontrib which works with ASP.Net MVC 3Oracle Destination via ODP.Net (Custom Destination Component): SSIS 2008 R2 solution (custom destination component) to write to oracle via ODP.NetOrchard Commerce History with PayPal: Project expands on Nwazet.Commerce module (and is required for this module to work). Adds a purchase history, product role associations, and PayPal.Phoenix Trans: Web Phoenix Trans v?n t?i hàng hóa trong và ngoài nu?cPowerState: PowerState is .NET application for sending Wake-On-LAN (WOL) requests to computers. It can also shutdown, log off and reboot computers using the WMI.RenameApp: RenameApp is a free and very simple to use renaming software for Windows. RenameApp allows you to easily rename files based on the specified criteria and order.Rose-Hulman User Experience Design: This project will contain labs intended for use in Rose-Hulman's Computer Science and Software Engineering department.Server d? phòng: Ðây là server d? phòng, SharePoint BCS External Connector Caching Pattern Library: Library for enabling caching on SharePoint BCS external connectors. Enables BCS .Net Assemblies to be written that are scalable and performant for search.SharpDX.WPF: This projects provides a DirectX 9, DirectX 10 and DirectX 11 support for WPF. The assembly contains DXElement - an easy to use WPF-FrameworkElement.Simple Password Generator Library: The password generator library, written in C#, is a simple assembly which allow generation of passwords with length anywhere from 1-99.SisEagle.NET: Esse sistema foi desenvolvido pra fins de apresentação do TCC referente ao ano de 2012 na UDF-BrasiliaSWebshop: SWebshop is a PHP based webshop system which allows you to insert, edit and delete data easily and is easy to use for customers.Tabular Database Powershell Cmdlets: This project provides a sample of PowerShell Cmdlets to manage Tabular models, from Analysis Services.University timetable using java: the project is using java language to create timetable (full timetable with exam tables and labs tables) and it will be free for all users with sql databaseURLShoter: This project for shorting URL for ASP.NETWeb Input Form Control: This control allow developer to create the input form by configuring the control in html modeWeibo: rtWorkoutMemo: Project descritpion(first draft): Memorise your workout. Keep archive records of your daily trening such: - series of excercise, - quantity of each serie, - weWPF - Automate Acrobat Security Policy: This WPF Tool was created to quickly password protect batches of PDF documents, using a random generator to generate the passwords.XiaoKyun: Hello Page for Web.Z3: Z3 is a high-performance theorem prover being developed at Microsoft Research.

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