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  • bool as object vs string as object testing equality

    - by Ray Pendergraph
    I am relatively new to C# and I noticed something interesting today that I guess I have never noticed or perhaps I am missing something. Here is an NUnit test to give an example: object boolean1 = false; object booloan2 = false; Assert.That(boolean1 == booloan2); This unit test fails, but this one passes: object string1 = "string"; object string2 = "string"; Assert.That(string1 == string2); I'm not that surprised in and of itself that the first one fails seeing as boolean1 and boolean2 are different references. But it is troubling to me that the first one fails and the second one passes. I read (on MSDN somewhere) that some magic was done to the String class to facilitate this. I think my question really is why wasn't this behavior replicated in bool? As a note... if the boolean1 and 2 are declared as "bool" then there is no problem. Does anyone know the reason for these differences or why it was implemented that way? Can anyone think of a situation where you would want to reference a bool object for anything except its value?

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  • How to specify allowed exceptions in WCF's configuration file?

    - by tucaz
    Hello! I´m building a set of WCF services for internal use through all our applications. For exception handling I created a default fault class so I can return treated message to the caller if its the case or a generic one when I have no clue what happened. Fault contract: [DataContract(Name = "DefaultFault", Namespace = "http://fnac.com.br/api/2010/03")] public class DefaultFault { public DefaultFault(DefaultFaultItem[] items) { if (items == null || items.Length== 0) { throw new ArgumentNullException("items"); } StringBuilder sbItems = new StringBuilder(); for (int i = 0; i Specifying that my method can throw this exception so the consuming client will be aware of it: [OperationContract(Name = "PlaceOrder")] [FaultContract(typeof(DefaultFault))] [WebInvoke(UriTemplate = "/orders", BodyStyle = WebMessageBodyStyle.Bare, ResponseFormat = WebMessageFormat.Json, RequestFormat = WebMessageFormat.Json, Method = "POST")] string PlaceOrder(Order newOrder); Most of time we will use just .NET to .NET communication with usual binds and everything works fine since we are talking the same language. However, as you can see in the service contract declaration I have a WebInvoke attribute (and a webHttp binding) in order to be able to also talk JSON since one of our apps will be built for iPhone and this guy will talk JSON. My problem is that whenever I throw a FaultException and have includeExceptionDetails="false" in the config file the calling client will get a generic HTTP error instead of my custom message. I understand that this is the correct behavior when includeExceptionDetails is turned off, but I think I saw some configuration a long time ago to allow some exceptions/faults to pass through the service boundaries. Is there such thing like this? If not, what do u suggest for my case? Thanks a LOT!

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  • Entangled text boxes

    - by user38329
    Hi StackOverflow, A mere Windows textbox greatly surprised me today. I have two unrelated text boxes inside an application. I can type in either text box and switch the focus by clicking on them. Then happens some event X, which I can't describe here for reasons given below. After this event happens, the two text boxes become "entangled" in an almost quantum way. Say, text box A was focused before X happened. When I click text box B to type in some text, the new text appears in text box A, whereas the blinking cursor happily moves along in text box B through the void, as if the text were there. No amount of clicking on either text boxes can resolve this. The cursor will always remain in B, whereas the text will always go to A. Message spying reveals that after the event X, the text boxes lose the ability to lose or gain focus. When I click on B, WM_LOSE_FOCUS does not come to A, and WM_SET_FOCUS does not come to B. (The rectangles and visibility of the boxes are OK.) The same thing happens in Windows XP and Windows 7. Now, event X: it's a big event in a third-party UI library which I cannot reverse-engineer in a timely manner. (Namely, docking a pane in wxAUI.) I am sure that this behavior is the result of incorrect WinAPI calls to the text boxes (garbage in - garbage out). I would like to know what could possibly cause such "textbox trip" to know where to start looking for the bug. Thanks!

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  • MS Office Excel Ribbon - Cannot change/hide Editing group in Home tab

    - by A9S6
    I have a .net addin for Excel. The addin creates the Ribbon UI for Excel 2007 and re-purposes some existing commands such as Cut, Copy, Paste, Sort etc. For Cut, Copy and Paste I am just overriding their OnAction value to call my own procedure when the buttons are clicked. But for Sort, Sort Asc and Sort Desc commands the case is a little different. When either of the Sort, Sort Asc or Sort Desc buttons are clicked, I want to get notified and then call the default functionality. This was possible in Excel 2003 commandsbars by calling the Execute() method on the CommandBarControl. In Excel 2007, there is a ExecuteMso() method to programmatically click a ribbon element but when the OnAction is overridden, this ExecuteMso() method just executes my own procedure and not the default functionality of that button. So I thought that I will HIDE the Sort buttons in the "Editing" group in Home tab and add my own Sort, Sort Asc and Sort Desc buttons to it. The buttons will call into my procedure first from where I will call the default behavior. Now the problem is that I am unable to change/hide the Editing group (idMso="GroupEditing"). Is this built-in group not editable? I can however HIDE the Clipboard and other groups(but can't add buttons to them). <?xml version="1.0" encoding="UTF-8" standalone="yes"?> <customUI xmlns="http://schemas.microsoft.com/office/2006/01/customui"> <ribbon> <tabs> <tab idMso="TabHome"> <group idMso="GroupEditing" visible="false" /> </tab> </tabs> </ribbon> </customUI>

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  • FileReference.browse() stops playback on some Flash Players

    - by Christophe Herreman
    We have an issue were the server session associated with a Flex client times out when the browse file dialog is open for a time longer then the configured session timeout. It seems that on some players, the playback is stopped when browse or download on a FileReference is executing. This also causes remote calls to be blocked and hence our manual keep-alive messages are not sent to the server, resulting in a session timeout. I searched for some info on this in the docs and found a notice of it, but it does not explicitly list the players it does (not) work. Would anyone know were I could find a complete list? PS: here are the links that mention this behavior: http://livedocs.adobe.com/flex/3/html/help.html?content=17_Networking_and_communications_7.html While calls to the FileReference.browse(), FileReferenceList.browse(), or FileReference.download() method are executing, most players will continue SWF file playback. http://livedocs.adobe.com/flex/3/langref/flash/net/FileReference.html While calls to the FileReference.browse(), FileReferenceList.browse(), or FileReference.download() methods are executing, SWF file playback pauses in stand-alone and external versions of Flash Player and in AIR for Linux and Mac OS X 10.1 and earlier Anyone knows what is meant with an "external Flash Player"? PPS: we tested this on Linux (10.0.x and 10.1.x) in Firefox where it seems to stop playback and on Windows (10.0.x) in IE where playback seems to continue.

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  • How to reduce the need for IISRESET for developing ASP.NET web app in IIS 5.1

    - by John Galt
    I have a web application project on my dev PC running WinXP and hence IIS 5.1. The changes I'm making to this site seem to "take effect" only after I do IISRESET. That is, I make a source change, Rebuild the project and then Start without Debugging (or with debugging). The newly changed code is not "visible" or in effect unless I intervene with an IISRESET. BTW, the "web" tab on the Properties display for the web app project is configured to use the Local IIS web server at project Url: http://localhost/myVirtualDirectory ... but I've noticed the same issue when using the VStudio Dev Server (i.e. I have to stop it by visiting the taskbar tray area in order to see my source changes take effect). Is this something I can change? EDIT UPDATE: Just wanting to clear this up if possible. Two answers diverge below; not sure how to move forward. One states this is to be expected (weakness of IIS 5.1 which in turn is the best WinXP can provide). Another states this is not expected behavior (and I tend to agree since this is the first I've encounted this on the same old WinXP dev platform I've had a long time). I suspect it may be something "deep inside" the Visual Studio 2008 web app which was upgraded to this new IDE from VStudio 2002 (ASP.NET 1.1). I've tried to add comment/questions down each answer path. Thanks.

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  • "Subforms" associated with tree view in VB

    - by knomdeguerre
    I am using VB Express 2008 to demonstrate my ideas for an improved UI for an existing product for my colleagues at work. The current UI has a certain page with ten tabs, allowing the user to define up to ten "things". The available choices for each of the ten "things" are all the same. On each of the ten tabs, there is a checkbox to enable that definition. Generally, a user will never use more than 5 or 6 unique definitions, the rest will remain disabled. So far, my prototype has a tree view control with one branch to contain this list of definitions, Add and Delete buttons. My idea is: there is one sub-branch to start with (corresponding to the first tab in the current UI); if the user wants addtional definitions, they click Add and other branches are added to the tree view, up to maximum of ten. I think I should be able to create a "class" that has a sub-UI (like a sub-form in Access) along with behavior code, that can be instantiated with each press of the Add button; each instantiation's settings can be set independently and is displayed in the main UI form )in a panel or frame) when selected in the tree view. For example, suppose the user Adds to make a total of three definitions: the tree view now has three sub-branches, each of which presents the same sub-UI with settings that can be set specific to the selected sub-branch. I'm sure it's possible but not sure how to do it. I know a comprehensive "answer" might be complicated and long, but I may just need some quick hints to get underway - don't be shy! Thanks in advance!

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  • IntelliJ Doesn't Notice Changes in Interface

    - by yar
    [I've decided to give IntelliJ another go (to replace Eclipse), since its Groovy support is supposed to be the best. But back to Java...] I have an Interface that defines a constant public static final int CHANNEL_IN = 1; and about 20 classes in my Module that implement that interface. I've decided that this constant was a bad idea so I did what I do in Eclipse: I deleted the entire line. This should cause the Project tree to light up like a Christmas tree and all classes that implement that interface and use that constant to break. Instead, this is not happening. If I don't actually double-click on the relevant classes -- which I find using grep -- the module even builds correctly (using Build - Make Module). If I double-click on a relevant class, the error is shown both in the Project Tree and in the Editor. I am not able to replicate this behavior in small tests, but in large modules it works (incorrectly) this way. Is there some relevant setting in IntelliJ for this?

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  • How to use boost::transform_iterator to iterate over modifed std::map values?

    - by Frank
    I have an std::map, and I would like to define an iterator that returns modified values. Typically, a std::map<int,double>::iterator iterates over std::pair<int,double>, and I would like the same behavior, just the double value is multiplied by a constant. I tried it with boost::transform_iterator, but it doesn't compile: #include <map> #include <boost/iterator/transform_iterator.hpp> #include <boost/functional.hpp> typedef std::map<int,double> Map; Map m; m[100] = 2.24; typedef boost::binder2nd< std::multiplies<double> > Function; typedef boost::transform_iterator<Function, Map::value_type*> MultiplyIter; MultiplyIter begin = boost::make_transform_iterator(m.begin(), Function(std::multiplies<double>(), 4)); // now want to similarly create an end iterator // and then iterate over the modified map The error is: error: conversion from 'boost ::transform_iterator< boost::binder2nd<multiplies<double> >, gen_map<int, double>::iterator , boost::use_default, boost::use_default >' to non-scalar type 'boost::transform_iterator< boost::binder2nd<multiplies<double> >, pair<const int, double> * , boost::use_default, boost::use_default >' requested What is gen_map and do I really need it? I adapted the transform_iterator tutorial code from here to write this code ...

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  • How do I implement configurations and settings?

    - by Malvolio
    I'm writing a system that is deployed in several places and each site needs its own configurations and settings. A "configuration" is a named value that is necessary to a particular site (e.g., the database URL, S3 bucket name); every configuration is necessary, there is not usually a default, and it's typically string-valued. A setting is a named value but it just tweaks the behavior of the system; it's often numeric or Boolean, and there's usually some default. So far, I've been using property files or thing like them, but it's a terrible solution. Several times, a developer has added a requirement for a configuration but not added the value to file for the live configuration, so the new release passed all the tests, then failed when released to live. Better, of course, for every file to be compiled — so if there's a missing configuration, or one of the wrong type, it won't get past the compiler — and inject the site-specific class into the build for each site. As a bones, a Scala file can easy model more complex values, especially lists, but also maps and tuples. The downside is, the files are sometimes maintained by people who aren't developers, so it has to be pretty self-explanatory, which was the advantage of property files. (Someone explain XML configurations to me: all the complexity of a compilable file but the run-time risk of a property file.) What I'm looking for is an easy pattern for defining a group required names and allowable values. Any suggestions?

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  • CSS Clearing Floats

    - by Frank
    I'm making more of an effort to separate my html structure from presentation, but sometimes when I look at the complexity of the hacks or workarounds to make things work cross-browser, I'm amazed at huge collective waste of productive hours that are put into this. As I understand it, floats were never created for creating layouts, but because many layouts need a footer, that's how they're often being used. To clear the floats, you can add an empty div that clears both sides (div class="clear"). That is simple and works cross browser, but it adds "non-semantic" html rather than solving the presentation problem within the CSS. I realize this, but after looking at all of the solutions with their benefits and drawbacks, it seems to make more sense to go with the empty div (predictable behavior across browsers), rather than create separate stylesheets, including various css hacks and workarounds, etc. which would also need to change as CSS evolves. Is it o.k. to do this as long as you do understand what you're doing and why you're doing it? Or is it better to find the CSS workarounds, hacks and separate structure from presentation at all costs, even when the CSS presentation tools provided are not evolved to the point where they can handle such basic layout issues?

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  • For loop index out of range ArgumentOutOfRangeException when multithreading

    - by Lirik
    I'm getting some strange behavior... when I iterate over the dummyText List in the ThreadTest method I get an index out of range exception (ArgumentOutOfRangeException), but if I remove the threads and I just print out the text, then everything works fine. This is my main method: public static Object sync = new Object(); static void Main(string[] args) { ThreadTest(); Console.WriteLine("Press any key to continue."); Console.ReadKey(); } This method throws the exception: private static void ThreadTest() { Console.WriteLine("Running ThreadTest"); Console.WriteLine("Running ThreadTest"); List<String> dummyText = new List<string>() { "One", "Two", "Three", "Four", "Five", "Six", "Seven", "Eight", "Nine", "Ten"}; for (int i = 0; i < dummyText.Count; i++) { Thread t = new Thread(() => PrintThreadName(dummyText[i])); // <-- Index out of range?!? t.Name = ("Thread " + (i)); t.IsBackground = true; t.Start(); } } private static void PrintThreadName(String text) { Random rand = new Random(DateTime.Now.Millisecond); while (true) { lock (sync) { Console.WriteLine(Thread.CurrentThread.Name + " running " + text); Thread.Sleep(1000+rand.Next(0,2000)); } } } This does not throw the exception: private static void ThreadTest() { Console.WriteLine("Running ThreadTest"); List<String> dummyText = new List<string>() { "One", "Two", "Three", "Four", "Five", "Six", "Seven", "Eight", "Nine", "Ten"}; for (int i = 0; i < dummyText.Count; i++) { Console.WriteLine(dummyText[i]); // <-- No exception here } } Does anybody know why this is happening?

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  • Zend hostname route doesn't match when it has child routes

    - by talisker
    I am implementing an Admin module, which contains the following routes: 'router' => array( 'routes' => array( 'admin' => array( 'type' => 'Zend\Mvc\Router\Http\Hostname', 'options' => array( 'route' => ':subdomain.mydomain.local', 'constraints' => array( 'subdomain' => 'admin', ), 'defaults' => array( 'module' => '__NAMESPACE__', 'controller' => 'Admin\Controller\Index', 'action' => 'index', ), ), 'priority' => 9000, 'may_terminate' => true, 'child_routes' => array( 'users' => array( 'type' => 'Zend\Mvc\Router\Http\Literal', 'options' => array( 'route' => '/users', 'defaults' => array( 'module' => '__NAMESPACE__', 'controller' => 'Admin\Controller\Users', 'action' => 'index', ), ), ), ) ), ), ), And this is the home route configuration: 'home' => array( 'type' => 'Zend\Mvc\Router\Http\Literal', 'options' => array( 'route' => '/', 'defaults' => array( 'controller' => 'Application\Controller\Index', 'action' => 'index', ), ), ), When I try to access to http://admin.mydomain.com, the route match always with the homeroute, but if I remove all the child routes from the admin route, the behavior is correct and a http://admin.mydomain.com matches with the adminroute. Any idea?

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  • How to prevent ADO.NET from altering double values when it reads from Excel files

    - by Khnle
    I have the following rows in my Excel input file: Column1 Column2 0-5 3.040 6 2.957 7 2.876 and the following code which uses ADO.NET to read it: string fileName = "input.xls"; var connectionString = string.Format("Provider=Microsoft.Jet.OLEDB.4.0; data source={0}; Extended Properties=Excel 8.0;", fileName); var dbConnection = new OleDbConnection(connectionString); dbConnection.Open(); try { var dbCommand = new OleDbCommand("SELECT * FROM [Sheet1$]", dbConnection); var dbReader = dbCommand.ExecuteReader (); while (dbReader.Read()) { string col1 = dbReader.GetValue(0).ToString(); string col2 = dbReader.GetValue(1).ToString(); } } finally { dbConnection.Close(); } The results are very disturbing. Here's why: The values of each column in the first time through the loop: col1 is empty (blank) col2 is 3.04016411633586 Second time: col1 is 6 col2 is 2.95722928448829 Third time: col1 is 7 col2 is 2.8763272933077 The first problem happens with col1 in the first iteration. I expect 0-5. The second problem happens at every iteration with col2 where ADO.NET obviously alters the values as it reads them. How to stop this mal-behavior?

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  • How to check whether user is login in web application?

    - by Morgan Cheng
    I want to learn the whole details of web application authentication. So, I decided to write a CodeIgniter authentication library from scratch. Now, I have to make design decision about how to determine whether one user is login. Basically, after user input username & password pair. A cookie is set for this session, following navigations in the web application will not require username & password. The server side will check whether the session cookie is valid to determine whether current user is login. The question is: how to determine whether cookie is valid cookie issued from server side? I can image the most simple way is to have the cookie value stored in session status as well. For each HTTP request, compare the value from cookie and the value from server session. (Since CodeIgniter session library store session variables in cookies, it is not applicable without some tweak.) This method requires storage in server side. For huge web application that is deployed in multiple datacenters. It is possible that user input username & password when browsing in one datacenter, while he/she access the web application in another datacenter later. The expected behavior is that user just input username & password once. As a result, all datacenters should be able to access the session status. That is possible not applicable even the session status is stored in external storage such as database. I tried Google. I login Google with Asian proxy which is supposed to direct me to datacenters in Asian. Then I switch to North American proxy which should direct me to datacenters in North America. It recognize my login without asking username and password again. So, is there any way to determine whether user is login without server side session status?

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  • Invoking a method overloaded where all arguments implement the same interface

    - by double07
    Hello, My starting point is the following: - I have a method, transform, which I overloaded to behave differently depending on the type of arguments that are passed in (see transform(A a1, A a2) and transform(A a1, B b) in my example below) - All these arguments implement the same interface, X I would like to apply that transform method on various objects all implementing the X interface. What I came up with was to implement transform(X x1, X x2), which checks for the instance of each object before applying the relevant variant of my transform. Though it works, the code seems ugly and I am also concerned of the performance overhead for evaluating these various instanceof and casting. Is that transform the best I can do in Java or is there a more elegant and/or efficient way of achieving the same behavior? Below is a trivial, working example printing out BA. I am looking for examples on how to improve that code. In my real code, I have naturally more implementations of 'transform' and none are trivial like below. public class A implements X { } public class B implements X { } interface X { } public A transform(A a1, A a2) { System.out.print("A"); return a2; } public A transform(A a1, B b) { System.out.print("B"); return a1; } // Isn't there something better than the code below??? public X transform(X x1, X x2) { if ((x1 instanceof A) && (x2 instanceof A)) { return transform((A) x1, (A) x2); } else if ((x1 instanceof A) && (x2 instanceof B)) { return transform((A) x1, (B) x2); } else { throw new RuntimeException("Transform not implemented for " + x1.getClass() + "," + x2.getClass()); } } @Test public void trivial() { X x1 = new A(); X x2 = new B(); X result = transform(x1, x2); transform(x1, result); }

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  • WCF Custom SOAP Header Issues

    - by WayneC
    I'm trying to implement an endpoint behavior which injects a custom SOAP header into all messages to and from a service. I've gotten pretty close by implementing the approach from the accepted answer of this question: http://stackoverflow.com/questions/986455/wcf-wsdl-soap-header-on-all-operations/995951#995951 After implementing that solution, my custom SOAP header does indeed show up in the WSDL; however, when I try to call the methods on my service, I get the following exception/fault: <ExceptionDetail xmlns="http://schemas.datacontract.org/2004/07/System.ServiceModel" xmlns:i="http://www.w3.org/2001/XMLSchema-instance"> <HelpLink i:nil="true" /> <InnerException i:nil="true" /> <Message>Index was outside the bounds of the array.</Message> <StackTrace> at System.ServiceModel.Dispatcher.DataContractSerializerOperationFormatter.AddHeadersToMessage(Message message, MessageDescription messageDescription, Object[] parameters, Boolean isRequest) at System.ServiceModel.Dispatcher.OperationFormatter.SerializeReply(MessageVersion messageVersion, Object[] parameters, Object result) at System.ServiceModel.Dispatcher.DispatchOperationRuntime.SerializeOutputs(MessageRpc&amp; rpc) at System.ServiceModel.Dispatcher.DispatchOperationRuntime.InvokeBegin(MessageRpc&amp; rpc) at System.ServiceModel.Dispatcher.ImmutableDispatchRuntime.ProcessMessage5(MessageRpc&amp; rpc) at System.ServiceModel.Dispatcher.ImmutableDispatchRuntime.ProcessMessage4(MessageRpc&amp; rpc) at System.ServiceModel.Dispatcher.ImmutableDispatchRuntime.ProcessMessage3(MessageRpc&amp; rpc) at System.ServiceModel.Dispatcher.ImmutableDispatchRuntime.ProcessMessage2(MessageRpc&amp; rpc) at System.ServiceModel.Dispatcher.ImmutableDispatchRuntime.ProcessMessage1(MessageRpc&amp; rpc) at System.ServiceModel.Dispatcher.MessageRpc.Process(Boolean isOperationContextSet)</StackTrace> <Type>System.IndexOutOfRangeException</Type> </ExceptionDetail> Looking in Reflector at the DataContractSerializerOperationFormatter.AddHeadersToMessage method thats throwing the exception, leads me to believe that the following snippet is causing the problem...but I'm not sure why. MessageHeaderDescription description = (MessageHeaderDescription) headerPart.Description; object parameterValue = parameters[description.Index]; I think the last line above is throwing the exception. The parameters variable is from IDispatchFormatter.SerializeReply What's going on?!?!! Any help would be greatly appreciated...

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  • In Google Chrome, how do I bring an existing popup window to the front using javascript from the par

    - by brahn
    I would like to have a button on a web page with the following behavior: On the first click, open a pop-up. On later clicks, if the pop-up is still open, just bring it to the front. If not, re-open. The below code works in Firefox (Mac & Windows), Safari (Mac & Windows), and IE8. (I have not yet tested IE6 or IE7.) However, in Google Chrome (both Mac & Windows) later clicks fail to bring the existing pop-up to the front as desired. How can I make this work in Chrome? <head> <script type="text/javascript"> var popupWindow = null; var doPopup = function () { if (popupWindow && !popupWindow.closed) { popupWindow.focus(); } else { popupWindow = window.open("http://google.com", "_blank", "width=200,height=200"); } }; </script> </head> <body> <button onclick="doPopup(); return false"> create a pop-up </button> </body> Background: I am re-asking this question specifically for Google Chrome, as I think I my code solves the problem at least for other modern browsers and IE8. If there is a preferred etiquette for doing so, please let me know.

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  • Project builds skipped with Any CPU build platform

    - by JMarsch
    All: We are using Visual Studio 2010, and we have recently upgraded our workstations to Windows 7/64-bit. I have a question: When I create a new solution, it seems to want to use the x86 platform. If I change the solution to "any cpu" and then I add a new project to the solution, the project will not have an "any cpu" build option, and it will be deselected from building (in configuration manager). Something seems wrong here. Here's what I want to have (assuming that it is supported): I want my solutions' platforms to default to "Any CPU" (I believe that means that at JIT time, the assembly will be either x86 or 64-bit, based on the machine that loaded it). When I add a new project to the solution, I want for it to have an "any cpu" solution, and I want for that projec to build by default. (basically, the same behavior that we had in VS 2008 on 32-bit workstations). How do I do that? Is there some additional thing that I need to know now that I am using a 64-bit workstation?

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  • What happens to class members when malloc is used instead of new?

    - by Felix
    I'm studying for a final exam and I stumbled upon a curious question that was part of the exam our teacher gave last year to some poor souls. The question goes something like this: Is the following program correct, or not? If it is, write down what the program outputs. If it's not, write down why. The program: #include<iostream.h> class cls { int x; public: cls() { x=23; } int get_x(){ return x; } }; int main() { cls *p1, *p2; p1=new cls; p2=(cls*)malloc(sizeof(cls)); int x=p1->get_x()+p2->get_x(); cout<<x; return 0; } My first instinct was to answer with "the program is not correct, as new should be used instead of malloc". However, after compiling the program and seeing it output 23 I realize that that answer might not be correct. The problem is that I was expecting p2->get_x() to return some arbitrary number (whatever happened to be in that spot of the memory when malloc was called). However, it returned 0. I'm not sure whether this is a coincidence or if class members are initialized with 0 when it is malloc-ed. Is this behavior (p2->x being 0 after malloc) the default? Should I have expected this? What would your answer to my teacher's question be? (besides forgetting to #include <stdlib.h> for malloc :P)

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  • Javascript onclick() event bubbling - working or not?

    - by user1071914
    I have a table in which the table row tag is decorated with an onclick() handler. If the row is clicked anywhere, it will load another page. In one of the elements on the row, is an anchor tag which also leads to another page. The desired behavior is that if they click on the link, "delete.html" is loaded. If they click anywhere else in the row, "edit.html" is loaded. The problem is that sometimes (according to users) both the link and the onclick() are fired at once, leading to a problem in the back end code. They swear they are not double-clicking. I don't know enough about Javascript event bubbling, handling and whatever to even know where to start with this bizarre problem, so I'm asking for help. Here's a fragment of the rendered page, showing the row with the embedded link and associated script tag. Any suggestions are welcomed: <tr id="tableRow_3339_0" class="odd"> <td class="l"></td> <td>PENDING</td> <td>Yabba Dabba Doo</td> <td>Fred Flintstone</td> <td> <a href="/delete.html?requestId=3339"> <div class="deleteButtonIcon"></div> </a> </td> <td class="r"></td> </tr> <script type="text/javascript">document.getElementById("tableRow_3339_0").onclick = function(event) { window.location = '//edit.html?requestId=3339'; };</script>

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  • Setting Nullable Integer to String Containing Nothing yields 0

    - by Brian MacKay
    I've been pulling my hair out over some unexpected behavior from nullable integers. If I set an Integer to Nothing, it becomes Nothing as expected. If I set an Integer? to a String that is Nothing, it becomes 0! Of course I get this whether I explicitly cast the String to Integer? or not. I realize I could work around this pretty easily but I want to know what I'm missing. Dim NullString As String = Nothing Dim NullableInt As Integer? = CType(NullString, Integer?) 'Expected NullableInt to be Nothing, but it's 0! NullableInt = Nothing 'This works -- NullableInt now contains Nothing. How is this EDIT: Previously I had my code up here so without the explicit conversion to 'Integer?' and everyone seemed to be fixated on that. I want to be clear that this is not an issue that would have been caught by Option Strict On -- check out the accepted answer. This is a quirk of the string-to-integer conversion rules which predate nullable types, but still impact them.

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  • Unity: Replace registered type with another type at runtime

    - by gehho
    We have a scenario where the user can choose between different hardware at runtime. In the background we have several different hardware classes which all implement an IHardware interface. We would like to use Unity to register the currently selected hardware instance for this interface. However, when the user selects another hardware, this would require us to replace this registration at runtime. The following example might make this clearer: public interface IHardware { // some methods... } public class HardwareA : IHardware { // ... } public class HardwareB : IHardware { // ... } container.RegisterInstance<IHardware>(new HardwareA()); // user selects new hardware somewhere in the configuration... // the following is invalid code, but can it be achieved another way? container.ReplaceInstance<IHardware>(new HardwareB()); Can this behavior be achieved somehow? BTW: I am completely aware that instances which have already been resolved from the container will not be replaced with the new instances, of course. We would take care of that ourselves by forcing them to resolve the instance once again.

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  • how to set style through javascript in IE immediately

    - by rezna
    Hi, recently I've encountered a problem with IE. I have a function function() { ShowProgress(); DoSomeWork(); HideProgress(); } where ShowProgress and HideProgress just manipulate the 'display' CSS style using jQuery's css() method. In FF everything is OK, and at the same time I change the display property to block, progress-bar appears. But not in IE. In IE the style is applied, once I leave the function. Which means it's never shown, because at the end of the function I simply hide it. (if I remove the HideProgress line, the progress-bar appears right after finishing executing the function (more precisely, immediately when the calling functions ends - and so there's nothing else going on in IE)). Has anybody encountered this behavior? Is there a way to get IE to apply the style immediately? I've prepared a solution but it would take me some time to implement it. My DoSomeWork() method is doing some AJAX calls, and these are right now synchronous. I assume that making them asynchronous will kind of solve the problem, but I have to redesign the code a bit, so finding a solution just for applying the style immediately would much simplier. Thanks rezna

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  • How would you code an efficient Circular Buffer in Java or C#

    - by Cheeso
    I want a simple class that implements a fixed-size circular buffer. It should be efficient, easy on the eyes, generically typed. EDIT: It need not be MT-capable, for now. I can always add a lock later, it won't be high-concurrency in any case. Methods should be: .Add and I guess .List, where I retrieve all the entries. On second thought, Retrieval I think should be done via an indexer. At any moment I will want to be able to retrieve any element in the buffer by index. But keep in mind that from one moment to the next Element[n] may be different, as the Circular buffer fills up and rolls over. This isn't a stack, it's a circular buffer. Regarding "overflow": I would expect internally there would be an array holding the items, and over time the head and tail of the buffer will rotate around that fixed array. But that should be invisible from the user. There should be no externally-detectable "overflow" event or behavior. This is not a school assignment - it is most commonly going to be used for a MRU cache or a fixed-size transaction or event log.

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