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  • Subview of custom NSView is resizing itself to fit within its superview

    - by Jonathan Patt
    I have a custom NSView which contains a subview—for the purposes of solving this issue, the top level view is simply acting as a container and automatically resizes to fit within the window. Its subview draws a rectangle 10 pixels inset from the edge of the window, except for the bottom, which should get clipped by the window until it's resized to show the entire rectangle. It does not, however, behave as I intend, and instead shrinks the height of the rectangle when its superview has a smaller height than it does. How do I avoid this and have it stay at its proper height and instead get clipped when the superview is smaller? The parent view's implementation code is: - (id)initWithFrame:(NSRect)frameRect { self = [super initWithFrame:frameRect]; if (self) { subView = [[SubView alloc] initWithFrame:frameRect]; } return self; } - (void)drawRect:(NSRect)dirtyRect { [[NSColor grayColor] set]; [subView setFrame:NSMakeRect(10, 10, dirtyRect.size.width - 20, 500)]; [self addSubview:subView]; } - (BOOL)isFlipped { return YES; } And the subview is just: - (void)drawRect:(NSRect)dirtyRect { [[NSColor blackColor] set]; [NSBezierPath strokeRect:dirtyRect]; } - (BOOL)isFlipped { return YES; }

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  • Scalaz: request for use case

    - by oxbow_lakes
    This question isn't meant as flame-bait! As it might be apparent, I've been looking at Scalaz recently. I'm trying to understand why I need some of the functionality that the library provides. Here's something: import scalaz._ import Scalaz._ type NEL[A] = NonEmptyList[A] val NEL = NonEmptyList I put some println statements in my functions to see what was going on (aside: what would I have done if I was trying to avoid side effects like that?). My functions are: val f: NEL[Int] => String = (l: NEL[Int]) => {println("f: " + l); l.toString |+| "X" } val g: NEL[String] => BigInt = (l: NEL[String]) => {println("g: " + l); BigInt(l.map(_.length).sum) } Then I combine them via a cokleisli and pass in a NEL[Int] val k = cokleisli(f) =>= cokleisli(g) println("RES: " + k( NEL(1, 2, 3) )) What does this print? f: NonEmptyList(1, 2, 3) f: NonEmptyList(2, 3) f: NonEmptyList(3) g: NonEmptyList(NonEmptyList(1, 2, 3)X, NonEmptyList(2, 3)X, NonEmptyList(3)X) RES: 57 The RES value is the character count of the (String) elements in the final NEL. Two things occur to me: How could I have known that my NEL was going to be reduced in this manner from the method signatures involved? (I wasn't expecting the result at all) What is the point of this? Can a reasonably simple and easy-to-follow use case be distilled for me? This question is a thinly-veiled plea for some lovely person like retronym to explain how this powerful library actually works.

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  • Returning ifstream in a function

    - by wrongusername
    Here's probably a very noobish question for you: How (if at all possible) can I return an ifstream from a function? Basically, I need to obtain the filename of a database from the user, and if the database with that filename does not exist, then I need to create that file for the user. I know how to do that, but only by asking the user to restart the program after creating the file. I wanted to avoid that inconvenience for the user if possible, but the function below does not compile in gcc: ifstream getFile() { string fileName; cout << "Please enter in the name of the file you'd like to open: "; cin >> fileName; ifstream first(fileName.c_str()); if(first.fail()) { cout << "File " << fileName << " not found.\n"; first.close(); ofstream second(fileName.c_str()); cout << "File created.\n"; second.close(); ifstream third(fileName.c_str()); return third; //compiler error here } else return first; } EDIT: sorry, forgot to tell you where and what the compiler error was: main.cpp:45: note: synthesized method ‘std::basic_ifstream<char, std::char_traits<char> >::basic_ifstream(const std::basic_ifstream<char, std::char_traits<char> >&)’ first required here EDIT: I changed the function to return a pointer instead as Remus suggested, and changed the line in main() to "ifstream database = *getFile()"; now I get this error again, but this time in the line in main(): main.cpp:27: note: synthesized method ‘std::basic_ifstream<char, std::char_traits<char> >::basic_ifstream(const std::basic_ifstream<char, std::char_traits<char> >&)’ first required here

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  • C# - WinForms - Exception Handling for Events

    - by JustLooking
    Hi all, I apologize if this is a simple question (my Google-Fu may be bad today). Imagine this WinForms application, that has this type of design: Main application - shows one dialog - that 1st dialog can show another dialog. Both of the dialogs have OK/Cancel buttons (data entry). I'm trying to figure out some type of global exception handling, along the lines of Application.ThreadException. What I mean is: Each of the dialogs will have a few event handlers. The 2nd dialog may have: private void ComboBox_SelectedIndexChanged(object sender, EventArgs e) { try { AllSelectedIndexChangedCodeInThisFunction(); } catch(Exception ex) { btnOK.enabled = false; // Bad things, let's not let them save // log stuff, and other good things } } Really, all the event handlers in this dialog should be handled in this way. It's an exceptional-case, so I just want to log all the pertinent information, show a message, and disable the okay button for that dialog. But, I want to avoid a try/catch in each event handler (if I could). A draw-back of all these try/catch's is this: private void someFunction() { // If an exception occurs in SelectedIndexChanged, // it doesn't propagate to this function combobox.selectedIndex = 3; } I don't believe that Application.ThreadException is a solution, because I don't want the exception to fall all the way-back to the 1st dialog and then the main app. I don't want to close the app down, I just want to log it, display a message, and let them cancel out of the dialog. They can decide what to do from there (maybe go somewhere else in the app). Basically, a "global handler" in between the 1st dialog and the 2nd (and then, I suppose, another "global handler" in between the main app and the 1st dialog). Thanks.

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  • Nested dereferencing arrows in Perl: to omit or not to omit?

    - by DVK
    In Perl, when you have a nested data structure, it is permissible to omit de-referencing arrows to 2d and more level of nesting. In other words, the following two syntaxes are identical: my $hash_ref = { 1 => [ 11, 12, 13 ], 3 => [31, 32] }; my $elem1 = $hash_ref->{1}->[1]; my $elem2 = $hash_ref->{1}[1]; # exactly the same as above Now, my question is, is there a good reason to choose one style over the other? It seems to be a popular bone of stylistic contention (Just on SO, I accidentally bumped into this and this in the space of 5 minutes). So far, none of the usual suspects says anything definitive: perldoc merely says "you are free to omit the pointer dereferencing arrow". Conway's "Perl Best Practices" says "whenever possible, dereference with arrows", but it appears to only apply to the context of dereferencing the main reference, not optional arrows on 2d level of nested data structures. "MAstering Perl for Bioinfirmatics" author James Tisdall doesn't give very solid preference either: "The sharp-witted reader may have noticed that we seem to be omitting arrow operators between array subscripts. (After all, these are anonymous arrays of anonymous arrays of anonymous arrays, etc., so shouldn't they be written [$array-[$i]-[$j]-[$k]?) Perl allows this; only the arrow operator between the variable name and the first array subscript is required. It make things easier on the eyes and helps avoid carpal tunnel syndrome. On the other hand, you may prefer to keep the dereferencing arrows in place, to make it clear you are dealing with references. Your choice." Personally, i'm on the side of "always put arrows in, since itg's more readable and obvious tiy're dealing with a reference".

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  • Looking for ideas how to refactor my (complex) algorithm

    - by _simon_
    I am trying to write my own Game of Life, with my own set of rules. First 'concept', which I would like to apply, is socialization (which basicaly means if the cell wants to be alone or in a group with other cells). Data structure is 2-dimensional array (for now). In order to be able to move a cell to/away from a group of another cells, I need to determine where to move it. The idea is, that I evaluate all the cells in the area (neighbours) and get a vector, which tells me where to move the cell. Size of the vector is 0 or 1 (don't move or move) and the angle is array of directions (up, down, right, left). This is a image with representation of forces to a cell, like I imagined it (but reach could be more than 5): Let's for example take this picture: Forces from lower left neighbour: down (0), up (2), right (2), left (0) Forces from right neighbour : down (0), up (0), right (0), left (2) sum : down (0), up (2), right (0), left (0) So the cell should go up. I could write an algorithm with a lot of if statements and check all cells in the neighbourhood. Of course this algorithm would be easiest if the 'reach' parameter is set to 1 (first column on picture 1). But what if I change reach parameter to 10 for example? I would need to write an algorithm for each 'reach' parameter in advance... How can I avoid this (notice, that the force is growing potentialy (1, 2, 4, 8, 16, 32,...))? Can I use specific design pattern for this problem? Also: the most important thing is not speed, but to be able to extend initial logic. Things to take into consideration: reach should be passed as a parameter i would like to change function, which calculates force (potential, fibonacci) a cell can go to a new place only if this new place is not populated watch for corners (you can't evaluate right and top neighbours in top-right corner for example)

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  • How to prepopulate an Outlook MailItem and avoiding a com Exception from the object model guard

    - by torrente
    Hi, I work for a company that develops a CRM tool and offers integration with MS Office(2003 & 2007) from windows XP to 7. (I'm working using Win7) My task is to call an Outlook instance (using C#) from this CRM tool when the user wants to send an email and prepopulate with data of the CRM tool (email, recipient, etc..) All of this already works just fine. The problem I'm having is that Outlook's "object model guard" is throwing com Exception (Operation aborted (Exception from HRESULT: 0x80004004 (E_ABORT))) the moment I try to read a protected value from the mailItem (such as mail.bodyHTML). Example Snippet: using MSOutlook = Microsoft.Office.Interop.Outlook; //untrusted Instance _outlook = new MSOutlook.Application(); MSOutlook.MailItem mail = (MSOutlook.MailItem)_outlook.CreateItem(MSOutlook.OlItemType.olMailItem); //this where the Exception occurs string outlookStdHTMLBody = mail.HTMLBody; I've done quite a bit of reading and know that my Outlook Instance (derived by using new Application) is considered untrusted and therefore the "omg" kicks in. I do have a workaround for development: I'm running VS2010 as Administrator and if I run Outlook as Administrator as well - all is good. I suppose this is due to them having the same integrity levels(high) and the UAC(?) is not complaining. But that just ain't the way to go for deployment. Now the question is: Is there a way to obtain a trusted instance of Outlook so that I can avoid this exception? I've already read that when developing an Office Add-In using VSTO one can obtain a trusted Instance from the OnComplete event and/or using "ThisAddin" But I "merely" want to start an outlook instance and preopulate it, and do not want to develop an Add-In since this is not the requirement. And to make it clear - I have no problem with pop ups informing the user that outlook is being accessed - I just want to get rid of the exception! So how can I get around this problem using code? Any help is highly appreciated! Thomas

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  • Django Class Views and Reverse Urls

    - by kalhartt
    I have a good many class based views that use reverse(name, args) to find urls and pass this to templates. However, the problem is class based views must be instantiated before urlpatterns can be defined. This means the class is instantiated while urlpatterns is empty leading to reverse throwing errors. I've been working around this by passing lambda: reverse(name, args) to my templates but surely there is a better solution. As a simple example the following fails with exception: ImproperlyConfigured at xxxx The included urlconf mysite.urls doesn't have any patterns in it mysite.urls from mysite.views import MyClassView urlpatterns = patterns('', url(r'^$' MyClassView.as_view(), name='home') ) views.py class MyClassView(View): def get(self, request): home_url = reverse('home') return render_to_response('home.html', {'home_url':home_url}, context_instance=RequestContext(request)) home.html <p><a href={{ home_url }}>Home</a></p> I'm currently working around the problem by forcing reverse to run on template rendering by changing views.py to class MyClassView(View): def get(self, request): home_url = lambda: reverse('home') return render_to_response('home.html', {'home_url':home_url}, context_instance=RequestContext(request)) and it works, but this is really ugly and surely there is a better way. So is there a way to use reverse in class based views but avoid the cyclic dependency of urlpatterns requiring view requiring reverse requiring urlpatterns...

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  • NullPointerException and the best way to deal with it

    - by lupin
    Note: This is homework/assignment feel not to answer if you don't want to. Ok after some search and reading these: http://stackoverflow.com/questions/425439/how-to-check-if-array-element-is-null-to-avoid-nullpointerexception-in-java http://stackoverflow.com/questions/963936/gracefully-avoiding-nullpointerexception-in-java http://c2.com/cgi/wiki?NullPointerException Am still not making any progress on how to deal with NullPointerException error on my code, snippet for questionable code: int findElement(String element) { int retval = 0; for ( int i = 0; i < setElements.length; i++) { if ( setElements[i].equals(element) ) { // This line 31 here return retval = i; } else { return retval = -1; } } return retval; } void add(String newValue) { int elem = findElement(newValue); if( numberOfElements < maxNumberOfElements && elem != -1 ) { setElements[numberOfElements] = newValue; numberOfElements++; } else { System.out.println("Element " + newValue + "already exist"); } } It compile but adding new element to a set throws a NullPointerException error. D:\javaprojects>java SetDemo Enter string element to be added A You entered A Exception in thread "main" java.lang.NullPointerException at Set.findElement(Set.java:31) at Set.add(Set.java:44) at SetDemo.main(Set.java:145) I added another check, though honestly don't have clue if this right to line 31. if ( setElements != null && setElements[i].equals(element) ) but still no joy. A documentation/tips or explanation is greatly appreciated. learning, lupin

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  • WPF TextBox Interceping RoutedUICommands

    - by Joseph Sturtevant
    I am trying to get Undo/Redo keyboard shortcuts working in my WPF application (I have my own custom functionality implemented using the Command Pattern). It seems, however, that the TextBox control is intercepting my "Undo" RoutedUICommand. What is the simplest way to disable this so that I can catch Ctrl+Z at the root of my UI tree? I would like to avoid putting a ton of code/XAML into each TextBox in my application if possible. The following briefly demonstrates the problem: <Window x:Class="InputBindingSample.Window1" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:loc="clr-namespace:InputBindingSample" Title="Window1" Height="300" Width="300"> <Window.CommandBindings> <CommandBinding Command="loc:Window1.MyUndo" Executed="MyUndo_Executed" /> </Window.CommandBindings> <DockPanel LastChildFill="True"> <StackPanel> <Button Content="Ctrl+Z Works If Focus Is Here" /> <TextBox Text="Ctrl+Z Doesn't Work If Focus Is Here" /> </StackPanel> </DockPanel> </Window> using System.Windows; using System.Windows.Input; namespace InputBindingSample { public partial class Window1 { public static readonly RoutedUICommand MyUndo = new RoutedUICommand("MyUndo", "MyUndo", typeof(Window1), new InputGestureCollection(new[] { new KeyGesture(Key.Z, ModifierKeys.Control) })); public Window1() { InitializeComponent(); } private void MyUndo_Executed(object sender, ExecutedRoutedEventArgs e) { MessageBox.Show("MyUndo!"); } } }

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  • Combine NotifyIcon and ToolTip

    - by Greycrow
    I have been working with NotifyIcon in order to show an icon in the taskbar. This program has no Windows Form. I perhaps could create one and make it invisible but I was hoping to avoid it. The ToolTip functions attached to NotifyIcon are somewhat lacking, and one of the gurus here suggested I look at the ToolTip functionality. It is possible to attach ToolTip to a form. Is is possible to attach it to just the NotifyIcon? I'm trying do this: NotifyIcon CTicon = new NotifyIcon(); ToolTip toolTip = new ToolTip(); toolTip.SetToolTip(CTicon, "Test"); And I get the error "cannot convert from 'System.Windows.Forms.NotifyIcon' to 'System.Windows.Forms.Control'. Is there a way to convert? I also tried: toolTip.SetToolTip(CTicon.Container, "Test"); but a container is apparently not a valid control either. I apologize for my total lack of understanding of how this may or may not work. Thanks in advance.

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  • Ruby - Immutable Objects

    - by Chris Bunch
    I've got a highly multithreaded app written in Ruby that shares a few instance variables. Writes to these variables are rare (1%) while reads are very common (99%). What is the best way (either in your opinion or in the idiomatic Ruby fashion) to ensure that these threads always see the most up-to-date values involved? Here's some ideas so far that I had (although I'd like your input before I overhaul this): Have a lock that most be used before reading or writing any of these variables (from Java Concurrency in Practice). The downside of this is that it puts a lot of synchronize blocks in my code and I don't see an easy way to avoid it. Use Ruby's freeze method (see here), although it looks equally cumbersome and doesn't give me any of the synchronization benefits that the first option gives. These options both seem pretty similar but hopefully anyone out there will have a better idea (or can argue well for one of these ideas). I'd also be fine with making the objects immutable so they aren't corrupted or altered in the middle of an operation, but I don't know Ruby well enough to make the call on my own and this question seems to argue that objects are highly mutable.

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  • Average function without overflow exception

    - by Ron Klein
    .NET Framework 3.5. I'm trying to calculate the average of some pretty large numbers. For instance: using System; using System.Linq; class Program { static void Main(string[] args) { var items = new long[] { long.MinValue + 100, long.MinValue + 200, long.MinValue + 300 }; try { var avg = items.Average(); Console.WriteLine(avg); } catch (OverflowException ex) { Console.WriteLine("can't calculate that!"); } Console.ReadLine(); } } Obviously, the mathematical result is 9223372036854775607 (long.MaxValue - 200), but I get an exception there. This is because the implementation (on my machine) to the Average extension method, as inspected by .NET Reflector is: public static double Average(this IEnumerable<long> source) { if (source == null) { throw Error.ArgumentNull("source"); } long num = 0L; long num2 = 0L; foreach (long num3 in source) { num += num3; num2 += 1L; } if (num2 <= 0L) { throw Error.NoElements(); } return (((double) num) / ((double) num2)); } I know I can use a BigInt library (yes, I know that it is included in .NET Framework 4.0, but I'm tied to 3.5). But I still wonder if there's a pretty straight forward implementation of calculating the average of integers without an external library. Do you happen to know about such implementation? Thanks!! UPDATE: The previous example, of three large integers, was just an example to illustrate the overflow issue. The question is about calculating an average of any set of numbers which might sum to a large number that exceeds the type's max value. Sorry about this confusion. I also changed the question's title to avoid additional confusion. Thanks all!!

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  • Izpack: Creating custom panels

    - by bguiz
    Hi, I am trying to create a custom panel for an IzPack installer. This means that I have to extend IzPanel. However, it appears that if I do this, the extended panel needs to be in the com.izforge.izpack.panels package. Then I found this post, which stipulates that: As such, you must include installer.jar from the lib folder of IzPack in the build path of your custom panel project. Your custom panel /must/ extend com.izforge.izpack.installer.IzPanel. Furthermore, it /must/ reside in the com.izforge.izpack.panels package. On top of it all, your build jar's name /must/ be the same as the unqualified name of your custom panel class. I take issue with the 1st and 4th points. They imply that I have to create an additional JAR file for each custom IzPanel that I create. Also, I would have to modify the IzPack installation by adding these JARs to one of its subdirectories. Is this article outdated (2008) and can it be safely ignored, or is this still true? If not how can I avoid this and simply have the extended IzPanel on the classpath instead? Thank you!

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  • Detect if any USB drive is detected or if not using WinForm Application in Visual C#

    - by Pavan Kumar
    I want to do the following things in my application 1) I want to display whether any USB drive is inserted or not in my application to prompt the user to insert a USB drive. I just want to notify the user if any USB dirve is inserted else prompt him to insert one using a label or something (i want to avoid messagebox as it will keep appearing whenever a device is inserted or removed. It will be irritating for the end user) in my Visual C# WinForm Application. If any USB drive is present display "USB drive detected" in the label. The user may add one or more USB sticks but the status will remain same. When there is none then the status of the label will change to "No USB drives found.Please insert a USB drive". 2) When one or more USB drive is added the volume name with the drive letter for example "James(F:)" is added to the Combobox list. The combobox list also needs to remove the entry for the USB drive added in the list automatically when it is removed . So when there is no USB the list should be empty and the label will again prompt user to insert a USB stick or drive.

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  • WordPress > Optimizing a query to show recent posts with a "View All" link when postcount exceeds ma

    - by Scott B
    I have a setting in my theme that allows the site owner to set the maximum number of posts ($maxPosts) to display in a "Recent Posts" menu. I'm using a custom script to generate the recent posts (because the Recent Posts widget does not highlight the current page, which I need for my css). My menu also is set up to display a "View All" link below the post listing, but only if the actual post count is $maxposts I'm trying to work out the best method for getting the post count and comparing it to $maxposts in order to determine whether or not to show a "View All" link. I'm sure there's probably a better way, but here's my code. I'm looking to optimize it to support very large post counts... $cat=get_cat_ID('excludeFromRecentPosts'); $catHidden=get_cat_ID('hidden'); $myquery = new WP_Query(); $myquery->query(array( 'cat' => "-$cat,-$catHidden", 'post_not_in' => get_option('sticky_posts') )); $myrecentpostscount = $myquery->found_posts; if ($myrecentpostscount > 0) { //show the menu if ($myrecentpostscount > $maxPosts) { //show "View All" link } } I really only need to determine if the total post count from the query is greater than the maxPost setting in order to determine whether to show the "View All" link, so I'm wondering if, in the case there are thousands of posts matching the criteria, to avoid performance issues, I don't need to get a count of all of them. I just need to count up until the point of maxPosts + 1, and that's where I'm struggling a bit because the user could elect to make maxPosts = -1 which means they want to show all posts. But this would be impractical, so I would probably set a upper limit of 20...

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  • Optional route parameters in ASP.NET 4 RTM no longer work as before

    - by Simon_Weaver
    I upgraded my project to ASP.NET 4 RTM with ASP.NET MVC 2.0 RTM today. I was previously using ASP.NET 3.5 with ASP.NET MVC 2.0 RTM. Some of my routes don't work suddenly and I don't know why. I'm not sure if something changed between 3.5 and 4.0 - or if this was a regression type issue in the 4.0 RTM. (I never previously tested my app with 4.0). I like to use Url.RouteUrl("route-name", routeParams) to avoid ambiguity when generating URLs. Here's my route definition for a gallery page. I want imageID to be optional (you get a thumbnail page if you don't specify it). // gallery id routes.MapRoute( "gallery-route", "gallery/{galleryID}/{imageID}/{title}", new { controller = "Gallery", action = "Index", galleryID = (string) null, imageID = (string) null, title = (string) null} ); In .NET 3.5 / ASP.NET 2.0 RTM / IIS7 Url.RouteUrl("gallery-route", "cats") => /gallery/cats Url.RouteUrl("gallery-route", "cats", 4) => /gallery/cats/4 Url.RouteUrl("gallery-route", "cats", 4, "tiddles") => /gallery/cats/4/tiddles In .NET 4.0 RTM / ASP.NET 2.0 RTM / IIS7 Url.RouteUrl("gallery-route", "cats") => null Url.RouteUrl("gallery-route", "cats", 4) => /gallery/cats/4 Url.RouteUrl("gallery-route", "cats", 4, "tiddles") => /gallery/cats/4/tiddles Previously I could supply only the galleryID and everything else would be ignored in the generated URL. But now it's looking like I need to specify all the parameters up until title - or it gives up in determining the URL. Incoming URLs work fine for /gallery/cats and that is correctly mapped through this rule with imageID and title both being assigned null in my controller. I also tested the INCOMING routes with http://haacked.com/archive/2008/03/13/url-routing-debugger.aspx and they all work fine.

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  • How to fix RapidXML String ownership concerns?

    - by Roddy
    RapidXML is a fast, lightweight C++ XML DOM Parser, but it has some quirks. The worst of these to my mind is this: 3.2 Ownership Of Strings. Nodes and attributes produced by RapidXml do not own their name and value strings. They merely hold the pointers to them. This means you have to be careful when setting these values manually, by using xml_base::name(const Ch *) or xml_base::value(const Ch *) functions. Care must be taken to ensure that lifetime of the string passed is at least as long as lifetime of the node/attribute. The easiest way to achieve it is to allocate the string from memory_pool owned by the document. Use memory_pool::allocate_string() function for this purpose. Now, I understand it's done this way for speed, but this feels like an car crash waiting to happen. The following code looks innocuous but 'name' and 'value' are out of scope when foo returns, so the doc is undefined. void foo() { char name[]="Name"; char value[]="Value"; doc.append_node(doc.allocate_node(node_element, name, value)); } The suggestion of using allocate_string() as per manual works, but it's so easy to forget. Has anyone 'enhanced' RapidXML to avoid this issue?

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  • How many files in a directory is too many?

    - by Kip
    Does it matter how many files I keep in a single directory? If so, how many files in a directory is too many, and what are the impacts of having too many files? (This is on a Linux server.) Background: I have a photo album website, and every image uploaded is renamed to an 8-hex-digit id (say, a58f375c.jpg). This is to avoid filename conflicts (if lots of "IMG0001.JPG" files are uploaded, for example). The original filename and any useful metadata is stored in a database. Right now, I have somewhere around 1500 files in the images directory. This makes listing the files in the directory (through FTP or SSH client) take a few seconds. But I can't see that it has any affect other than that. In particular, there doesn't seem to be any impact on how quickly an image file is served to the user. I've thought about reducing the number of images by making 16 subdirectories: 0-9 and a-f. Then I'd move the images into the subdirectories based on what the first hex digit of the filename was. But I'm not sure that there's any reason to do so except for the occasional listing of the directory through FTP/SSH.

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  • NHibernate Legacy Database Mappings Impossible?

    - by Corey Coogan
    I'm hoping someone can help me with mapping a legacy database. The problem I'm describing here has plagued others, yet I was unable to find a real good solution around the web. DISCLAIMER: this is a legacy DB. I have no control over the composite keys. They suck and can't be changed no matter much you tell me they suck. I have 2 tables, both with composite keys. One of the keys from one table is used as part of the key to get a collection from the other table. In short, the keys don't fully match between the table. ClassB is used everywhere I would like to avoid adding properties for the sake of this mapping if possible. public class ClassA { //[PK] public string SsoUid; //[PK] public string PolicyNumber; public IList<ClassB> Others; //more properties.... } public class ClassB { //[PK] public string PolicyNumber; //[PK] public string PolicyDateTime; //more properties } I want to get an instance of ClassA and get all ClassB rows that match PolicyNumber. I am trying to get something going with a one-to-many, but I realize that this may technically be a many-to-many that I am just treating as one-to-many. I've tried using an association class but didn't get far enough to see if it works. I'm new to these more complex mappings and am looking for advice. I'm open to pretty much any ideas. Thanks, Corey

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  • Why can't c# use inline anonymous lambdas or delegates?

    - by Samuel Meacham
    I hope I worded the title of my question appropriately. In c# I can use lambdas (as delegates), or the older delegate syntax to do this: Func<string> fnHello = () => "hello"; Console.WriteLine(fnHello()); Func<string> fnHello2 = delegate() { return "hello 2"; }; Console.WriteLine(fnHello2()); So why can't I "inline" the lambda or the delegate body, and avoid capturing it in a named variable (making it anonymous)? // Inline anonymous lambda not allowed Console.WriteLine( (() => "hello inline lambda")() ); // Inline anonymous delegate not allowed Console.WriteLine( (delegate() { return "hello inline delegate"; })() ); An example that works in javascript (just for comparison) is: alert( (function(){ return "hello inline anonymous function from javascript"; })() ); Which produces the expected alert box. UPDATE: It seems you can have an inline anonymous lambda in C#, if you cast appropriately, but the amount of ()'s starts to make it unruly. // Inline anonymous lambda with appropriate cast IS allowed Console.WriteLine( ((Func<string>)(() => "hello inline anonymous lambda"))() ); Perhaps the compiler can't infer the sig of the anonymous delegate to know which Console.WriteLine() you're trying to call? Does anyone know why this specific cast is required?

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  • Solutions for working with multiple branches in ASP.Net

    - by Corey McKinnon
    At work, we are often working on multiple branches of our product at one time. For example, right now, we have a maintenance branch, a branch with code just going to QA, and a branch for a new major initiative, that won't be merged for some time now. Our web project is set up to use IIS, so every time we switch to a different branch, we have to go in to IIS Admin and change the path on the virtual directory, then reset IIS, and sometimes even restart Visual Studio, to avoid getting build errors. Is there any way to simplify this, other than not having our web project set up as a virtual directory? I'm not sure we want to make that change at this point. What do you do to make this easier, assuming you do this? Corey @RedWolves, virtual machines would definitely work, but I'm not sure it would be any simpler, especially for some of the other developers on my team, which is partly why I'm looking for more simplicity. @Dan, we're not able to change source control providers, unfortunately. @pix0r, that's something I'll try when I get back to work. Thanks for the suggestion. @Haacked, I'll have to give that a try too, but I think we have some issues with why that won't work (I can't remember exactly why right now; this application was originally written in .Net 1.1, pre-Cassini, and I can't remember if we tried it when we upgraded to 2.0 or not). Thanks all for the responses so far.

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  • Detect if any USB drive is detected or not using WinForm Application in Visual C#

    - by Pavan Kumar
    I want to do the following things in my application 1) I want to display whether any USB drive is inserted or not in my application to prompt the user to insert a USB drive. I just want to notify the user if any USB dirve is inserted else prompt him to insert one using a label or something (i want to avoid messagebox as it will keep appearing whenever a device is inserted or removed. It will be irritating for the end user) in my Visual C# WinForm Application. If any USB drive is present display "USB drive detected" in the label. The user may add one or more USB sticks but the status will remain same. When there is none then the status of the label will change to "No USB drives found.Please insert a USB drive". 2) When one or more USB drive is added the volume name with the drive letter for example "James(F:)" is added to the Combobox list. The combobox list also needs to remove the entry for the USB drive added in the list automatically when it is removed . So when there is no USB the list should be empty and the label will again prompt user to insert a USB stick or drive.

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  • Adding AJAX call to function triggered popup blocker

    - by jerrygarciuh
    Hi folks, I have a client who wants to open variously sized images in a centered popup. I tried to get them to use FancyBox but they don't want interstitial presentation, so... I initially was opening a generic popup which resized and centered onload based on image size but they don't like the shift so I added a PHP script to echo the sizes and used jQuery to fetch the size info to feed into the pop up call. But it appears the delay this causes is setting off all popup blockers. Here is the JS $("#portfolioBigPic").click(function () { var src = $("#portfolioBigPic").attr('src'); var ar = src.split('/'); var fname = ar.pop(); fname = '/g/portfolio/clients/big/' + fname; $.get("imgsize.php", { i: fname}, function(data){ var dim = data.split(","); popit(fname,dim[0],dim[1]); }); }); function popit(img,w,h) { var features = 'width='+w+',height='+h+', toolbar=0, location=0, directories=0, status=0, menubar=0, scrollbars=0, resizable=1,'; var left = (screen.width/2)-(w/2); var top = 0; features += 'top='+top+',left='+left; bigpic = window.open('portfolioBigPic.php?img='+img, 'bigpic',features); bigpic.focus(); } The only difference between dodging the blockers and failing is that I added the AJAX .get and use it to specify w and h. Any thoughts on how to avoid this? Maybe I should use PHP to get widths and heights of all the big pics and write a JS array of them when this page loads? Am I right that the delay caused by fetching the data is tripping the blockers? Thoughts? Any advice much appreciated. JG

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  • IoC - Dynamic Composition of object instances

    - by Joshua Starner
    Is there a way using IoC, MEF [Imports], or another DI solution to compose dependencies on the fly at object creation time instead of during composition time? Here's my current thought. If you have an instance of an object that raises events, but you are not creating the object once and saving it in memory, you have to register the event handlers every time the object is created. As far as I can tell, most IoC containers require you to register all of the classes used in composition and call Compose() to make it hook up all the dependencies. I think this may be horrible design (I'm dealing with a legacy system here) to do this due to the overhead of object creation, dependency injection, etc... but I was wondering if it was possible using one of the emergent IoC technologies. Maybe I have some terminology mixed up, but my goal is to avoid writing a framework to "hook up all the events" on an instance of an object, and use something like MEF to [Export] handlers (dependencies) that adhere to a very specific interface and [ImportMany] them into an object instance so my exports get called if the assemblies are there when the application starts. So maybe all of the objects could still be composed when the application starts, but I want the system to find and call all of them as the object is created and destroyed.

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