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  • Pylons FormEncode @validate decorator pass parameters into re-render action

    - by joelbw
    I am attempting to use the validate decorator in Pylons with FormEncode and I have encountered an issue. I am attempting to validate a form on a controller action that requires parameters, and if the validation fails, the parameters aren't passed back in when the form is re-rendered. Here's an example. def question_set(self, id): c.question_set = meta.Session.query(QuestionSet).filter_by(id=id).first() c.question_subjects = meta.Session.query(QuestionSubject).order_by(QuestionSubject.name).all() return render('/derived/admin/question_set.mako') This is the controller action that contains my form. The form will add questions to an existing question set, which is identified by id. My add question controller action looks like this: @validate(schema=QuestionForm(), form='question_set', post_only=True) def add_question(self): stuff... Now, if the validation fails FormEncode attempts to redisplay the question_set form, but it does not pass the id parameter back in, so the question set form will not render. Is it possible to pass the id back in with the @validate decorator, or do I need to use a different method to achieve what I am attempting to do?

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  • How to post a file via HTTP post in vb.net

    - by Worz
    Hi all! Having a problem with sending a file via HTTP post in vb.net. I am trying to mimic the following HTML so the vb.net does the same thing. <form enctype="multipart/form-data" method="post" action="/cgi-bin/upload.cgi"> File to Upload: <input type="file" name="filename"/> <input type="submit" value="Upload" name="Submit"/> </form> Hope someone can help!

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  • Dynamic programming - Coin change decision problem?

    - by Tony
    I'm reviewing some old notes from my algorithms course and the dynamic programming problems are seeming a bit tricky to me. I have a problem where we have an unlimited supply of coins, with some denominations x1, x2, ... xn and we want to make change for some value X. We are trying to design a dynamic program to decide whether change for X can be made or not (not minimizing the number of coins, or returning which coins, just true or false). I've done some thinking about this problem, and I can see a recursive method of doing this where it's something like... MakeChange(X, x[1..n this is the coins]) for (int i = 1; i < n; i++) { if ( (X - x[i] ==0) || MakeChange(X - x[i]) ) return true; } return false; Converting this a dynamic program is not coming so easily to me. How might I approach this?

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  • JTwitter OAuth signpost example

    - by RenegadeAndy
    Hey. I believe JTwitter supports OAuth to authenticate against a developer account , however i cannot get any of them working. The JTwitter docs say signpost is the supported method - yet I cannot seem to find the OAuthSignpostClient class they use even after adding the signpost libs: OAuthSignpostClient client = new OAuthSignpostClient(JTWITTER_OAUTH_KEY, JTWITTER_OAUTH_SECRET, "oob"); Twitter jtwit = new Twitter("yourtwittername", client); // open the authorisation page in the user's browser client.authorizeDesktop(); // get the pin String v = client.askUser("Please enter the verification PIN from Twitter"); client.setAuthorizationCode(v); // Optional: store the authorisation token details Object accessToken = client.getAccessToken(); // use the API! jtwit.setStatus("Messing about in Java"); Has anybody code that code segment working? Please help Andy

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  • onload script does not work in subview page in JSF

    - by jackrobert
    Hi, Here i write two jsp page like outerPage.jsp and innerPage.jsp The outer page include innerPage.jsp The inner page have one textfield and one button.. I need focus for textFiled while page loading(innerPage.jsp).. I write a javascript, but not work it... The code is outerPage.jsp <%@page contentType="text/html" pageEncoding="UTF-8"% <%@ taglib uri="http://java.sun.com/jsf/core" prefix="f" % <%@ taglib uri="http://java.sun.com/jsf/html" prefix="h" % <%@ taglib uri="http://richfaces.org/a4j" prefix="a4j" % <%@ taglib uri="http://richfaces.org/rich" prefix="rich"% <f:view> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>Outer Viewer</title> <meta name="description" content="Outer Viewer" /> </head> <body id="outerMainBody"> <rich:page id="richPage"> <rich:layout> <rich:layoutPanel position="center" width="100*"> <a4j:outputPanel> <f:verbatim><table style="padding: 5px;"><tbody><tr> <td> <jsp:include page="innerPage.jsp" flush="true"/> </td> </tr></tbody></table></f:verbatim> </a4j:outputPanel> </rich:layoutPanel> </rich:layout> </rich:page> </body> </f:view> innerPage.jsp <%@page contentType="text/html" pageEncoding="UTF-8"% <%@ taglib uri="http://java.sun.com/jsf/core" prefix="f" % <%@ taglib uri="http://java.sun.com/jsf/html" prefix="h" % <%@ taglib uri="http://richfaces.org/a4j" prefix="a4j" % <%@ taglib uri="http://richfaces.org/rich" prefix="rich"% <f:subview id="innerViewerSubviewId"> <f:verbatim><head> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> <title>Inner Viewer </title> <script type="text/javascript"> //This script does not called during the page loading (onload) function cursorFocus() { alert("Cursor Focuse Method called..."); document.getElementById("innerViewerForm:innerNameField").focus(); alert("Cursor Focuse method end!!!"); } </script> </head> <body onload="cursorFocus();"></f:verbatim> <h:form id="innerViewerForm"> <rich:panel id="innerViewerRichPanel"> <f:facet name="header"> <h:outputText value="Inner Viewer" /> </f:facet> <a4j:outputPanel id="innerViewerOutputPanel" > <h:panelGrid id="innerViewerSearchGrid" columns="2" cellpadding="3" cellspacing="3"> //<%-- Row 1 For Text Field --%> <h:outputText value="inner Name : " /> <h:inputText id="innerNameField" value=""/> //<%-- Row 2 For Test Button --%> <h:outputText value="" /> <h:commandButton value="TestButton" action="test" /> </h:panelGrid> </a4j:outputPanel> </rich:panel> </h:form> <f:verbatim></body></f:verbatim> </f:subview> <f:verbatim></html></f:verbatim> The cursorFocus script does not called... Here i need cursor focus for textFiled after display the page ... Thanks in advance.

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  • Need Help with Jquery TableSorter Pager plugin.

    - by chobo2
    Hi I am using the tablesorter plugin: http://tablesorter.com/docs/ with jquery 1.4.2 Now my problem is this. The user can dynamically add rows to the table. But this seems to mess up the paging. Like first it gets added to the first "page" of rows but if you would go to the second page and you go back to the first page. You newly record is gone. I don't know where it goes but it is just gone. I tried to do this $('#pagerid').unbind('click'); $('#tbl tbody ').append(response.HtmlRow); $('#tbl').trigger('update'); So I tried to unbind the pager click method and do a trigger update but that does not seem to work. I then tried to add this line after the above 3 lines. $('#tbl').tablesorterPager({ container: $('#pagerid') }); but it seems to do nothing too. http://tablesorter.com/docs/example-pager.html

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  • Delphi 2010 Error Insight incorrectly flags "Undeclared Identifier"

    - by user257188
    In D2010, Error Insight is incorrectly underlining in red types like "TOpenDialog" (even though my unit and project's uses both include Dialogs). Also, in my method TMyFrame.Foo, it fails the same way by flagging a reference to a VCL component in my TMyFrame -- even though Foo and the component are both part of TMyFrame. SO suggested I read several threads on this subject. One mentions a D2009 fix for this. Is there a D2010 fix? Other postings have suggested that Error Insight yields too many false alarms and should just be turned off. Any suggestions?

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  • LIST<> AddRange throwing ArgumentException

    - by Tim
    Hi all, I have a particular method that is occasionally crashing with an ArgumentException: Destination array was not long enough. Check destIndex and length, and the array's lower bounds.: at System.Array.Copy(Array sourceArray, Int32 sourceIndex, Array destinationArray, Int32 destinationIndex, Int32 length, Boolean reliable) at System.Collections.Generic.List`1.CopyTo(T[] array, Int32 arrayIndex) at System.Collections.Generic.List`1.InsertRange(Int32 index, IEnumerable`1 collection) at System.Collections.Generic.List`1.AddRange(IEnumerable`1 collection) The code that is causing this crash looks something like this: List<MyType> objects = new List<MyType>(100); objects = FindObjects(someParam); objects.AddRange(FindObjects(someOtherParam); According to MSDN, List<.AddRange() should automatically resize itself as needed: If the new Count (the current Count plus the size of the collection) will be greater than Capacity, the capacity of the List<(Of <(T)) is increased by automatically reallocating the internal array to accommodate the new elements, and the existing elements are copied to the new array before the new elements are added. Can someone think of a circumstance in which AddRange could throw this type of exception?

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  • Overlay WriteableBitmap with color

    - by rajenk
    I'm trying to overlay a WriteableBitmap with a certain color in Silverlight. I have a black and white base image, which I'm using to create smaller WriteableBitmap images for a new composite image and I want to overlay either the black or white part of the source image cut-out with a certain color before adding it to the composite image. What I'm doing now is: var cutOut = new WriteableBitmap(8, 14); /* cut out the image here */ cutOut.Render(sourceImage, transform); // sourceImage is the base image cutOutImage.Source = cutOut; // cutOutImage is an Image element in XAML compositeImage.Render(cutOutImage, transform2); // compositeImage is the final WriteableBitmap that is shown on screen I tried the methods on http://blogs.silverarcade.com/silverlight-games-101/15/silverlight-blitting-and-blending-with-silverlights-writeablebitmap/ and using the extension methods from hxxp://writeablebitmapex.codeplex.com/, but I cannot seem to get a color overlay on the cutOut image before rendering it to the compositeImage. Does anyone know of a good method to do this? Thanks in advance.

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  • Unable to sync custom authentication with RIA services in SL3 + RIA implementation

    - by Nair
    I am developing SL3 + RIA services with custom authentication. I followed the example in http://code.msdn.microsoft.com/RiaServices/Release/ProjectReleases.aspx?ReleaseId=2661 to implement custom authentication. Based on the implementation, you first do login request from client to service. This request is async process. Noe the client GUI will start to bind data to SL controls using RIA services, which requires the authentication to be successful (by adding [RequireAuthentication] attribute). The trouble is, since you requested login from the main process, while it is doing authentication, the page control takes over and starts to bind data using RIA services. But the problem is authentication is not completed yet thus which ever the first service method data binding hits will fail with 'Access denied'. Bottom line is GUI is will not wait for authentication to be completed to start the data binding. My question is how do you handle this situation? Thanks,

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  • WCF Data Services consuming data from EF based repository

    - by John Kattenhorn
    We have an existing repository which is based on EF4 / POCO and is working well. We want to add a service layer using WCF Data Services and looking for some best practice advice. So far we have developed a class which has a IQueryable property and the getter triggers the repository 'get all users' method. The problem so far have been two-fold: 1) It required us to decorate the ID field of the poco object to tell data service what field was the id. This now means that our POCO object is not 'pure'. 2) It cannot figure out the relationships between the objects (which is obvious i guess). I've now stopped this approach and i'm thinking that maybe we should expose the OBjectContext from the repository and use more 'automatic' functionality of EF. Has anybody got any advice or examples of using the repository pattern with WCF Data Services ?

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  • How to access uploaded files in Ruby

    - by Jeff King
    I am trying use a Java Uploader in a ROR app (for its ease of uploading entire directories). The selected uploader comes with some PHP code that saves the files to the server. I am trying to translate this code to Ruby, but am stumped on this point: PHP has a very convenient superglobal – $_FILES – that contains a hash of all files uploaded to the current script via the HTTP POST method. It appears Ruby does not have a similar resource. Lacking that, what is the best way to access and save the uploaded files? I am using the JavaPowUpload uploader ( http://www.element-it.com/OnlineHelpJavaPowUpload/index.html ).

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  • Create Excel (.XLS and .XLSX) file from C#

    - by mistrmark
    What is the best tool for creating an Excel Spreadsheet with C#. Ideally, I would like open source so I don't have to add any third party dependencies to my code, and I would like to avoid using Excel directly to create the file (using OLE Automation.) The .CSV file solution is easy, and is the current way I am handling this, but I but I would like to control the output formats. EDIT: I am still looking at these to see the best alternative for my solution. Interop will work, but it requires Excel to be on the machine you are using. Also the OLEDB method is intriguing, but may not yield much more than what I can achieve with CSV files. I will look more into the 2003 xml format, but that also puts a Excel 2003 requirement on the file. I am currently looking at a port of the PEAR (PHP library) Excel Writer that will allow some pretty good XLS data and formatting and it is in the Excel_97 compatible format that all modern versions of Excel support. The PEAR Excel Writer is here: PEAR - Excel Writer

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  • "NOT_SUPPORTED_BY_GUI" Exception in JCo

    - by cedar715
    We are having a BAPI that uploads the specified document to SAP. The BAPI accept three parameters: ID, FILE_LOC and FOLDER_NAME. And I'm setting the values as follows in the JCo code: JCO.ParameterList paramList = function.getImportParameterList(); paramList.setValue("101XS1", "EXTERNAL_ID"); paramList.setValue("tmp", "FOLDER_NAME"); paramList.setValue("D:/upload/foo.txt", "FILE_LOCATION"); But when I'm trying to execute the BAPI, am getting the following exception: com.sap.mw.jco.JCO$Exception: (104) RFC_ERROR_SYSTEM_FAILURE: Exception condition "NOT_SUPPORTED_BY_GUI" raised. at com.sap.mw.jco.rfc.MiddlewareRFC$Client.nativeExecute(Native Method) at com.sap.mw.jco.rfc.MiddlewareRFC$Client.execute(MiddlewareRFC.java:1242) at com.sap.mw.jco.JCO$Client.execute(JCO.java:3816) at com.sap.mw.jco.JCO$Client.execute(JCO.java:3261) The same BAPI is working fine if I execute through thick client(SAP Logon). But through JCo, its giving this error.

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  • How can I add a prefix to a WCF ServiceContract Namespace

    - by Lodewijk
    Hi, I'm trying to implement an UPnP MediaServer in WCF. I'm slowly getting there, but now I've hit a brick wall. I need to add a prefix to the ServiceContract namespace. Right now I have the following: [ServiceContract(Namespace = "urn:schemas-upnp-org:service:ContentDirectory:1")] public interface IContentDirectory { [OperationContract(Action = "urn:schemas-upnp-org:service:ContentDirectory:1#Browse")] void Browse(string ObjectID, string BrowseFlag, string Filter, ulong StartingIndex, ulong RequestedCount, string SortCriteria, out string Result, out ulong NumberReturned, out ulong TotalMatches, out ulong UpdateID); } This listens to the correct soap-messages. However, I need the soap-body to begin with <u:Browse xmlns-u="urn:schemas-upnp-org:service:ContentDirectory:1"> and WCF is now listening to: <Browse xmlns="urn:schemas-upnp-org:service:ContentDirectory:1"> How do I get the prefix there? Does it matter? Or is there another reason why the parameters are not passed into the Browse method?

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  • How to list all (groovy) classes in JVM in groovy

    - by Dan
    I am writing a DelegatingMetaClass that I would like to apply to all groovy classes in my project, but I do not how to get hold of all classes in the project? Here is the code: /* This will work ok, since I know Foo beforehand, but what about classes that do not exist yet? */ def myMetaClass = new DelegatingMetaClass(Foo.class) InvokerHelper.metaRegistry.setMetaClass(Foo.class, myMetaClass) /* how to do this? allGroovyClasses.each{ def myMetaClass = new DelegatingMetaClass(it) InvokerHelper.metaRegistry.setMetaClass(it, myMetaClass) } */ class SimpleInterceptor extends DelegatingMetaClass{ public SimpleInterceptor(final Class aclass) { super(aclass); initialize(); } public Object getProperty(Object object, String prop) { println ("I am in a property interceptor!!!") return super.getProperty(object, prop) } public Object invokeMethod(Object a_object, String a_methodName, Object[] a_arguments) { println ("I am in a method interceptor!!!") return super.invokeMethod(a_object, a_methodName, a_arguments) }

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  • Error while using PowerMockito.whenNew()

    - by Ankush
    I am using PowerMockito(1.3.6) with Mockito(1.8.3) and Junit(4.7) for testing. I am quite stuck on an error: [junit] Testcase: testNextPNRFromQueueHappyPath(com.orbitz.galileo.host.robot.GalpoQueueConnectionTest): Caused an ERROR [junit] org/mockito/internal/IMockHandler [junit] java.lang.NoClassDefFoundError: org/mockito/internal/IMockHandler [junit] at org.powermock.api.mockito.internal.expectation.DefaultConstructorExpectationSetup.createNewSubsituteMock(DefaultConstructorExpectationSetup.java:80) [junit] at org.powermock.api.mockito.internal.expectation.DefaultConstructorExpectationSetup.withArguments(DefaultConstructorExpectationSetup.java:48) [junit] at com.orbitz.galileo.host.robot.GalpoQueueConnectionTest.testNextPNRFromQueueHappyPath(GalpoQueueConnectionTest.java:62) [junit] at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) [junit] at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) [junit] at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) My class under test : GalpoQueueConnection is basically creating a new object of another class : QueueReadBuilder. I am trying to do something like: @RunWith(PowerMockRunner.class) @PrepareForTest({GalpoQueueConnection.class, ApolloProcUtils.class}) public class GalpoQueueConnectionTest extends TestCase{ @Test public void testNextPNRFromQueueHappyPath() throws Exception { QueueReadBuilder mockBuilder = mock(QueueReadBuilder.class); PowerMockito.whenNew(QueueReadBuilder.class).withArguments(anyString(), anyString(), anyString()).thenReturn(mockBuilder); } } It seems like somehow powermockito is trying to call IMockHandler, and I looked at Mockito 1.8.3 api, and there isn't any. Any suggestions/ clues would be welcome.

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  • iphone setting UITextView delegate breaks auto completion

    - by Tristan
    Hi there! I have a UITextField that I would like to enable auto completion on by: [self.textView setAutocorrectionType:UITextAutocorrectionTypeYes]; This works normally, except when I give the UITextView a delegate. When a delegate is set, auto complete just stops working. The delegate has only the following method: - (void)textViewDidChange:(UITextView *)textView { self.textView.text = [self.textView.text stringByReplacingOccurrencesOfString:@"\n" withString:@""]; int left = LENGTH_MAX -[self.textView.text length]; self.characterCountLabel.text = [NSString stringWithFormat:@"%i",abs(left)]; } Does anyone know how to have both auto complete enabled and a delegate set? Thanks!Tristan

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  • refresh user control inside multiview

    - by daisy
    In my parentpage I have dropdownlist, multiview and button. Multiview has a user control. On click of the button i pass the selected value from dropdown to the user control and call the databind method to populate the user control with corresponding data. User control has gridview which is populated using objectDataSource. I'm using the ObjectCreating (ObjectDataSource) to set the objectInstance. 1st time everything works fine. But when the dropdown selection is changed and the button is clicked again then the user control does not refresh. What do I need to do so that the user control refreshed each time the drop down selection is changed. All the help is appreciated Thanks

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  • The parameters dictionary contains a null entry for parameter 'productId' of non-nullable type 'Syst

    - by Naim
    Hi Guys, I am trying to implement an edit page in order administrator to modify data in database.Unfortunately I am encountering an error. The code below: public ViewResult Edit(int productId) { // Do something here } but I am getting this error: "The parameters dictionary contains a null entry for parameter 'productId' of non-nullable type 'System.Int32' for method 'System.Web.Mvc.ViewResult Edit(Int32)' in 'WebUI.Controllers.AdminController'. To make a parameter optional its type should be either a reference type or a Nullable type. Parameter name: parameters" I changed my route in Global.asax.cs like this: routes.MapRoute( "Admin", "Admin/{action}/{ productId}", new { controller = "Admin", action = "Edit", productId= "" } ); but still I am getting the error Thanks for your help! Naim

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  • CATiledLayer: Determining levelsOfDetail when in drawLayer

    - by Russell Quinn
    I have a CATiledLayer inside a UIScrollView and all is working fine. Now I want to add support for showing different tiles for three levels of zooming. I have set levelsOfDetail to 3 and my tile size is 300 x 300. This means I need to provide three sets of tiles (I'm supplying PNGs) to cover: 300 x 300, 600 x 600 and 1200 x 1200. My problem is that inside "(void)drawLayer:(CALayer *)layer inContext:(CGContextRef)ctx" I cannot work out which levelOfDetail is currently being drawn. I can retrieve the bounds currently required by using CGContextGetClipBoundingBox and usually this requests a rect for one of the above sizes, but at layer edges the tiles are usually smaller and therefore this isn't a good method. Basically, if I have set levelsOfDetail to 3, how do I find out if drawLayer is requesting level 1, 2 or 3 when it's called? Thanks, Russell.

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  • Deleting blog post using Blogger API, Javascript and Prototype

    - by Mikhail
    Hello, everyone! I'm trying to delete a blog post on blogger.com using Blogger API via Prototype Javascript library. Here's my code: var request = new Ajax.Request( 'http://www.blogger.com/feeds/'+remoteBlogId+'/posts/default/'+postId { method:'DELETE', requestHeaders:['Authorization', 'GoogleLogin auth='+authKey], on200:function(){/*onSuccess*/}, onFailure:function(){/*onFailure*/} } ); As far as I can see from API description, everything's alright, but when I run this, it fires onSuccess function, but doesn't delete the entry on the server. I guess that Prototype doesn't work well with HTTP methods other than GET and POST (here's the ticket describing similar problem though proposed patch didn't work for me) Any help is appreciated! Thanks in advance, Mikhail.

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  • C# - Screenshot of process under Windows Service

    - by Jonathan.Peppers
    We have to run a process from a windows service and get a screenshot from it. We tried the BitBlt and PrintWindow Win32 calls, but both give blank (black) bitmaps. If we run our code from a normal user process, it works just fine. Is this something that is even possible? Or could there be another method to try? Things we tried: Windows service running as Local System, runs process as Local System - screenshot fails Windows service running as Administrator, runs process as Administrator - screenshot fails. Windows application running as user XYZ, runs a process as XYZ - screenshot works with both BitBlt or PrintWindow. Tried checking "Allow service to interact with desktop" from Local System We also noticed that PrintWindow works better for our case, it works if the window is behind another window. For other requirements, both the parent and child processes must be under the same user. We can't really use impersonation from one process to another.

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  • MDI WinForm application and duplicate child form memory leak

    - by Steve
    This is a WinForm MDI application problem (.net framework 3.0). It will be described in C#. Sorry it is a bit long because I try to make things as clear as possible. I have a MDI application. At some point I find that one MDI child form is never released. There is a menu that creates the MDI child form and show it. When the MDI child form is closed, it is supposed to be destroyed and the memory taken by it should be given back to .net. But to my surprise, this is not true. All the MDI child form instances are kept in memory. This is obviously a "memory leak". Well, it is not a real leak in .net. It is just that I think the closed form should be dead but somehow there is at least one unknown reference from outside world that still connect with the closed form. I read some articles on the Web. Some says that when the MDI child form is closing, I should unwire all the event handlers, otherwise some event handlers may keep my form alive. Some says that DataBindings should be cleaned before the form is closing otherwise the DataBindings will add references to some global Hashtable and thus keep my form alive. My form contains quite a lot things. Many event handlers and many DataBindings and many BindingSources and few suspected controls containing user control and HelpProvider. I create a big method that unwires all the event handlers from all the relevant controls, clear all the DataBindings and DataSources. The HelpProvider and user controls are disposed carefully. At the end, I find that, I don't have to clear DataBindings and DataSources. Event handlers are definitely causing the problem. And MDI form structure also contributes to something. During my experiments, I find that, if you create a MDI child form, even if you close it, there will still be one instance in the memory. The reference is from PropertyStore of the main form. This means, unless the main form is closed (application ends), there will always be one instance of MDI child form in the memory. The good news is that, no matter how many times you open and close the child form, there will be only one instance, not a big "leak". When it comes to event handlers, things become more tricky. I have to address that, all the event handlers on my form are anonymous event handlers. Here is an example code: //On MDI child form's design code... Button btnSave = new Button(); btnSave.Click += new System.EventHandler(btnSave_Click); Where btnSave_Click is also a method in MDI child form. The above is always the case for various controls and various types of event. To me, this is a bi-directional circular reference. btnSave keeps a reference of MDI child form via the event handler. MDI child form keeps a reference of btnSave instance. To me again, such bi-directional circular reference should not cause any problem for .net's garbage collector. This means that I do not have to explicitly unwire the event when the form is being disposed: btnSave.Click -= btnSave_Click; But the truth is not so. For some event handlers, they are safe. Ignoring them do not cause any duplicate instance. For some other event handlers, they will cause one instance remaining in the memory (similar effect as the MDI form structure, but this time caused by the hanging event handlers). For some other event handlers, they will cause every instance opened in the memory. I am totally confused about the differences between these three types of event handlers. The controls are created in the same way and the event is attached in the same way. What is the difference? (Don't tell me it is the event handle methods that make difference.) Anyone has experience of this wired scenario and has an answer for me? Thanks a lot. So now, for safety issue, I will have to unwire all the event handlers when the form is being disposed. That will be a long list of similar code for each control. Is there a general way of removing events from controls in recursive way using reflection? What about performance issue? That's the end of my story and I am still in the middle of my problem. For any help, I thank you.

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  • Why doesn't EnumerableRowCollection<DataRow>.Select() compile like this?

    - by David Fox
    This works: from x in table.AsEnumerable() where x.Field<string>("something") == "value" select x.Field<decimal>("decimalfield"); but, this does not: from x in table.AsEnumerable() .Where(y=>y.Field<string>("something") == "value") .Select(y=>y.Field<decimal>("decimalfield")); I also tried: from x in table.AsEnumerable() .Where(y=>y.Field<string>("something") == "value") .Select(y=>new { name = y.Field<decimal>("decimalfield") }); Looking at the two overloads of the .Select() method, I thought the latter two should both return EnumerableRowCollection, but apparently I am wrong. What am I missing?

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