CallWindowProc NullReferenceException -- ParkingWindow

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- Previous
  - 1
    - Enjoying using Win Forms Really like using Win Forms with C#. C# is nice to use. I also like C++ but found MFC and Dialog based apps a bit more tricky to use. C# + Win Forms is a nice combo I think. Tag: CallWindowProc NullReferenceException -- ParkingWindow Tag: 105147
  - 2
    - Convert MDI to SDI We have an application written in VB6 which performs a lot of different functionality for a helpdesk (create orders, create invoices, manage employees, etc). It's written as an MDI application. Nearly everything I see says MDI is really not a great design choice and I somewhat agree with that. So, as we go over concepts for rewriting this app in .Net 2, I'm trying to come up with how to convert it to an SDI application. We have nearly 150 different mdi child forms in the app, about 30 of those are directly accessible from menu items, the others are forms that come up when using those 30 main function forms. Do you have a main form with your menus and task options which is always shown and then simply open the new functional forms as standard windows forms that will have their own taskbar item and menu bar, etc? (this seems like the type of interface that outlook uses - the main frame of the application and then a new form to write an email or open a task in). I think this is the right design method, I'm just having trouble wrapping my brain around the right method. Thanks for any ideas on how this should be designed. Tag: CallWindowProc NullReferenceException -- ParkingWindow Tag: 105144
  - 3
    - Problem in changing the custom icon for a Windows form using C#.NE I am trying to change the form icon of a C# windows application.I am using the Visual Studio .NET 2003 IDE. I have modified the icon using the icon editor available in Visual Studio .NET IDE. After saving my changes, when I try to update the Icon property of the main form , the icon image appears correctly in the Properties window but the icon image in the upper left corner of the form does not get updated. However, I don't find this issue in a windows application created using the Visual Basic.NET 2003 edition. Why is it that there is a mismatch ? Is this a bug in C#.NET 2003 edition ? Steps to reproduce the issue: 1. Open the VS.NET 2003 IDE and create a new C# Windows Application. 2. In the Solution Explorer window, right click on the project name and add a new Icon file. 3. Double click on the icon file added and modify it in the Icon editor. 4.Now change the Icon property of the main form to the icon file created and modified in steps 2&3. Actual Results The Icon image gets updated in the Properties window but the icon image in the upper left corner of the form does not get updated. Run the application and you will find that the form icon in the window caption is still not updated. Expected Results The modified Icon image should get updated in the upper left corner of the form window. Here are the configuration details of my development environment: Operating System : Windows XP Professional Microsoft .NET framework 1.1 Version 1.1.4322 Microsoft Development Environment 2003 Version 7.1.3088 Tag: CallWindowProc NullReferenceException -- ParkingWindow Tag: 105142
  - 4
    - ReportViewer with LocalReport: DataSource question Hi! I use a ReportViewer control to show a local report, defined as EmbeddedResource (RDLC). The report definition file (RDLC) uses a DataTable as DataSource. My intention is to find an efficient way to filter the data that is shown by the report. My first attempt was to set the filter on the BindingSource that is defined as ReportDataSource for the LocalReport.DataSources list of the ReportViewer. The code fragment created by the Designer looks like this: reportDataSource2.Name = "DataSet1_SomeDataTable"; reportDataSource2.Value = this.bindingSource1; this.reportViewer1.LocalReport.DataSources.Add(reportDataSource2); But when I set this.bindingSource1.Filter = "ID=1"; (for example) before calling RefreshReport(), this doesn't have any effect, the data shown by the report doesn't use the filter. Given the fact, that the report definition itself sets a DataSource (in the RDLC file), my question is: What is the true DataSource? What sense does it make that the ReportViewer defines a DataSource for the report that doesn't seem to be used? Further question: in case my observation (the DataSource defined by the ReportViewer not being used by the report) is true, how can I achieve an efficient filtering? By using report parameters? I hesitated to do this because I want to use a filter that can freely be defined (which doesn't seem to be possible with report parameters). Thanks a lot for any hint! -- Axel Hecker Tag: CallWindowProc NullReferenceException -- ParkingWindow Tag: 105141
  - 5
    - Force a WinForms User Control to unload, removing its delegate event handler from the invocation list of another class Here's a scenario: A Business class raises an event, which is handled by a custom WinForms UserControl. When the control is removed from the containing Form/Panel, it is not GCed because the Business class retains a pointer to the event handler delegate in the UserControl. Is there anyway, except from explicitly removing the delegate from the Business class' invocation list, to force the UserControl to unload (i.e. "implicitly" remove the delegate from the invocation list and make the UserControl eligable for GC)? Is there a some "best practice" to handle this kind of situation? In the example below, clicking "button 1" will display "here" in the Output Window, regardless if "button 2" was clicked or not. The "dispose" and nullification of the buttonEx1 in button2_click simply demonstrate that the form no longer references buttonEx1: // business class public class BL { public event EventHandler Notify; public void OnNotify() { if ( Notify != null) Notify(this, EventArgs.Empty); } } // custom usercontrol class ButtonEx : Button { public void set(BL b) { b.Notify += delegate { Debug.WriteLine("here"); }; } } // code in form ButtonEx buttonEx1; BL b; public Form1() { InitializeComponent(); b = new BL(); buttonEx1 = new ButtonEx(); this.buttonEx1.set(b); this.panel1.Controls.Add(buttonEx1); } private void button1_Click(object sender, EventArgs e) { this.b.OnNotify(); } // this code clears the panel where the custom ButtonEx resides in private void button2_Click(object sender, EventArgs e) { this.panel1.Controls.Clear(); buttonEx1.Dispose(); buttonEx1 = null; } Thanks. Tag: CallWindowProc NullReferenceException -- ParkingWindow Tag: 105139
  - 6
    - datagridview I have a DataGridView binded to an access datasource. I Would like that every cell had -1 as value will use a different style respect others cell. Any ideas ? tnx Tag: CallWindowProc NullReferenceException -- ParkingWindow Tag: 105137
  - 7
    - Best practice to display data received through event from external source. Hi, I am receiving objects in form of eventArguments through very frequent events from some external source. Better to say that we need to handle the flood of events, and process the object received from each event as soon as possible and wait for the new events. Right now I keep on adding the received objects in some Arraylist. I need to use the saved objects for calculation as well as for displaying on UI. I have used some of the following techniques to complete the job. Can I get comments or comparison among the points given below for increasing the performance. Any further improvements/suggestions are most welcome. 1) Use of the Generic List and Dictionary instead of ArrayList 2) Keep on adding the objects in an arraylist till a certain time limit (lets say 250 ms) and then forward the ArrayList through event to UI/class for display/calculation. Since shared arraylist acess can create issues(for filling data from events and fetching data to send), so I can use the following alernative methods ... a) Create 2 Arraylists. Fill first arraylist till a certain time limit, then set a bool variable and start filling alternate arraylist. Using the first arraylist for sending event to own UI and then clear this first arraylist. Next do same thing with alternate arraylist b) Whenever a time limit elaspes, use lock to access a arraylist and create clone. Use this clone for sending into the eventarg. 3) Firing so many events can bring down the system. So receive the data in some event from external source and keep adding into arraylist. External UI etc can fetch the data after certain interval by accessing a property wrapped arround a cache. Regards, Rajat. Tag: CallWindowProc NullReferenceException -- ParkingWindow Tag: 105136
  - 8
    - connecting asp.net with oracle9i Hello All, Can anyone here suggest me some idea for my following queries? 1) How do I connect asp.net with oracle9i? 2) How can I generate a report using Crystal Report with asp.net based on certain user conditions? Thanks in advance Jackfadd Tag: CallWindowProc NullReferenceException -- ParkingWindow Tag: 105135
  - 9
    - Key Press Event Never Get Fired!! Hi I have a very strange problem about my Key Press event never get fired in the VS2005. I have a parent form and a user control. In my user control, I add two text box. I also set two hot key for this two textbox. What I want to do is when the user press the hot key(eg, Alt+E) then the specific textbox will get the focus. But my problem this does not work at all, I have tried the keypress event , and also tried to overrided the onKeyPress event for both my user control and my parent form. Can anyone give me some info what is going on here? Tag: CallWindowProc NullReferenceException -- ParkingWindow Tag: 105133
  - 10
    - Load on demand Hi I'm looking for a magazine article about load on demand , i have seen it very recently (last month or so) but i don't recall which magazine. the article is about load on demand the problem we have is that our application takes a lot of time to load (80 seconds) because it loads all the forms and data at the start up . the article showed how to load the required information for the first form and would load the rest in a lower priority thread. but when calling a new form this would become the high priority info to retreave not sur if i'm clear enough any help would be appreciated on load on demand and let me know if you recall the magazine name and date thanks Tag: CallWindowProc NullReferenceException -- ParkingWindow Tag: 105131
  - 11
    - InvalidOperationException Hi I have an application in VS2003 (Frk1.1) and it works well. After I updated it to VS2005 (Frk2.0) and I run the application it shows the following message and exception: The Undo operation encountered a context that is different from what was applied in the corresponding Set operation. The possible cause is that a context was Set on the thread and not reverted(undone). System.InvalidOperationException was unhandled Message="The Undo operation encountered a context that is different from what was applied in the corresponding Set operation. The possible cause is that a context was Set on the thread and not reverted(undone)." Source="mscorlib" StackTrace: at System.Threading.SynchronizationContextSwitcher.Undo() at System.Threading.ExecutionContextSwitcher.Undo() at System.Threading.ExecutionContext.runFinallyCode(Object userData, Boolean exceptionThrown) at System.Runtime.CompilerServices.RuntimeHelpers.ExecuteBackoutCodeHelper(Object backoutCode, Object userData, Boolean exceptionThrown) at System.Runtime.CompilerServices.RuntimeHelpers.ExecuteCodeWithGuaranteedCleanup(TryCode code, CleanupCode backoutCode, Object userData) at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state) at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state) at System.Net.ContextAwareResult.Complete(IntPtr userToken) at System.Net.LazyAsyncResult.ProtectedInvokeCallback(Object result, IntPtr userToken) at System.Net.Sockets.BaseOverlappedAsyncResult.CompletionPortCallback(UInt32 errorCode, UInt32 numBytes, NativeOverlapped* nativeOverlapped) at System.Threading._IOCompletionCallback.PerformIOCompletionCallback(UInt32 errorCode, UInt32 numBytes, NativeOverlapped* pOVERLAP) I had seached and I guess the error is related with threads, and in fact in the form that shows the error I have some Forms.Timers. If someone can help me i'll be greateful!! Tag: CallWindowProc NullReferenceException -- ParkingWindow Tag: 105128
  - 12
    - TreeView control and nodes Hi there, I'm creating an AddIn and I'd like to construct a "TreeView" control whose nodes match those seen in Solution Explorer. Is there any way to get hold of these? Thanks very much. Tag: CallWindowProc NullReferenceException -- ParkingWindow Tag: 105125
  - 13
    - Publish Application in an ASPX page? Is it possible to publish a vb.net windows application as an aspx file (rather than a .htm) file? The real goal we are after is using then using the web.config file to control security to the deployment page (we would prefer this over NTFS permissions on the directory itself). Thanks in advance. Tag: CallWindowProc NullReferenceException -- ParkingWindow Tag: 105120
  - 14
    - Event to inform of ActiveControl changed? Hi: I am looking for a way to know when the user moves from one control to another on a WinForm. I don't want to hook the event handlers of all the child controls (GotFocus and LostFocus), but am looking for a more generic way of doing this. I have noticed that ErrorProvider knows exactly when the cursor is moved to another control on the same window, so there must be some way! TIA, Martin. Tag: CallWindowProc NullReferenceException -- ParkingWindow Tag: 105119
  - 15
    - Class Architecture I am using the Enterprise Library, specifically the Logging functionality. I would like to write a class that has protected methods which perform the actual logging of methods that are called and possibly raise events. My problem is I'm struggling with the design. I want to design this functionality in a fashion that I can be inherited by other classes (mainly base classes) for both UI contol classes and non UI classes. I have looked into the decorator pattern but this won't work as the inheritance of UI Base Classes start to cause problems. Does anyone have any thoughts on solving this? public class MethodLogging { protected virtual void OnMethodRequestBegin(MethodRequestEventArgs e) { //Log the Method Name using verbose logging (i.e. e.MethodName) //Raise an event to let other classes know a method was called } protected virtual void OnMethodRequestEnd (MethodRequestEventArgs e) { //Log the Method Name using verbose logging (i.e. e.MethodName) //Raise an event to let other classes know a method was called } } //Here is the problem, as C# doesn't allow multiple class inheritance public class BaseUIClass : Form, MethodLogging { public void MethodA() { OnMethodRequestBegin (new MethodRequestEventArgs ("MethodA")); //Do Work for Method A OnMethodRequestEnd (new MethodRequestEventArgs ("MethodA")); } } public class BaseClass : MethodLogging { public void MethodB() { OnMethodRequestBegin (new MethodRequestEventArgs ("MethodB")); //Do Work for Method B OnMethodRequestEnd (new MethodRequestEventArgs ("MethodB")); } } I have thought about using Interfaces, but then I still have to code the OnMethodRequestBegin and OnMethodRequestEnd for every single UI Control which duplicates the code all over the place instead of keeping everything in one nice neat package. I would like to come up with a solution that will work for both UI and non UI classes alike. Tag: CallWindowProc NullReferenceException -- ParkingWindow Tag: 105117
  - 16
    - ErrorProvider Property Hi, I know how to set the message for an ErrorProvider through code when handling a validating event, however, I would like to use the message that is entered at design time in the properties window for a given control. ie. Error or ErrorProvider1. How can I use this message with the seterror method? Tag: CallWindowProc NullReferenceException -- ParkingWindow Tag: 105111
  - 17
    - Multiple applications share one configuration file (ApplicationSet Is it possible to have multiple applications sharing one configuration file with the ApplicationSettingsBase class? If so how can i achieve this? Thanks Tag: CallWindowProc NullReferenceException -- ParkingWindow Tag: 105106
  - 18
    - MDI Children forms Hi, is it possible within an MDI based app to somehow get the Z-Orders of windows so it can be possible to save out the positions and order so the next time you ran the app the windows would be in the same state ? I've tried searching about z-order but it seems a no go area and things are just controlled by SendToXxx(), so is there any way of doing what I'm trying to do ? Regards, P Tag: CallWindowProc NullReferenceException -- ParkingWindow Tag: 105100
  - 19
    - How to determine if I am in a web or a windows application Hello to all, I use a lib class to handle all my exeption errors ocured in my objects. Since my objects are used in windows applications as well as in web applications, I would like to determine in my lib class if she is serving a web or a windows application. Is there a neat way to detect this. Greets Jean.Paul Tag: CallWindowProc NullReferenceException -- ParkingWindow Tag: 105097
  - 20
    - System.AccessViolationException running debugger Hello all! Sometimes, not consistently, focus change cause the WinForm application, running in debug mode, to throw following exception: ================================================== "System.AccessViolationException: Attempted to read or write protected memory. This is often an indication that other memory is corrupt. at System.Windows.Forms.UnsafeNativeMethods.CallWindowProc(IntPtr wndProc, IntPtr hWnd, Int32 msg, IntPtr wParam, IntPtr lParam) at System.Windows.Forms.NativeWindow.DefWndProc(Message& m) at System.Windows.Forms.ToolTip.WndProc(Message& msg) at System.Windows.Forms.ToolTip.ToolTipNativeWindow.WndProc(Message& m) at System.Windows.Forms.NativeWindow.DebuggableCallback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam) at System.Windows.Forms.UnsafeNativeMethods.DispatchMessageW(MSG& msg) at System.Windows.Forms.Application.ComponentManager.System.Windows.Forms.UnsafeNativeMethods.IMsoComponentManager.FPushMessageLoop(Int32 dwComponentID, Int32 reason, Int32 pvLoopData) at System.Windows.Forms.Application.ThreadContext.RunMessageLoopInner(Int32 reason, ApplicationContext context) at System.Windows.Forms.Application.ThreadContext.RunMessageLoop(Int32 reason, ApplicationContext context) at System.Windows.Forms.Application.Run(Form mainForm) at MqPlus.Gui.FrmMain.Main() in C:\Projects\MqPlus\MqPlus\FrmMain.cs:line 352" ================================================== The scenario is: run application (F5), switch to other application (Alt+Tab), switch vice versa to application. There is no unsafe code in application. There is no COM/COM+/or other not .NET libraries usage. Do someone have idea what may cause such exception? Thanks ahead Tag: CallWindowProc NullReferenceException -- ParkingWindow Tag: 105096
  - 21
    - ComboBox and Datasource I have a combobox that load its data from a dataset. After i had load data, i would like to add an element, to a combobox, in the first position. Whow do i do ? any ideas tnx Tag: CallWindowProc NullReferenceException -- ParkingWindow Tag: 105095
  - 22
    - TreeView node chopping off bold text in framework 1.1 I have a TreeView control and I populate nodes and set their text property. If I make the font of the tree node bold, the part of the last letter is chopped off when displayed. It seems like the length of the tree node label is tied to the normal look of the font, and since the bold view makes the text take mode place, the text is chopped off. Any ideas? . . TreeNode nodePrfTitle = new TreeNode("Preferred Name"); nodePrfTitle.ImageIndex = 2; nodePrfTitle.SelectedImageIndex = 2; nodePrfTitle.NodeFont = new System.Drawing.Font("Microsoft Sans Serif", 8.25F, System.Drawing.FontStyle.Bold, System.Drawing.GraphicsUnit.Point, ((System.Byte)(0))); . . Tag: CallWindowProc NullReferenceException -- ParkingWindow Tag: 105082
  - 23
    - Dire TreeView performance in .Net 2.0 vs 1.1 All, Microsoft appear to have changed the internal implementation of the TreeView control and the changes appear to be not for the better as far as my application is concerned. Has anyone else had performance issues with it? The issue I have is that I need to change the .Text and .ImageIndex of the nodes AFTER the tree has been populated. This is because the tree contains percentages etc based on the children of each node. In .Net 1.0/1.1 I had this finely tuned to do a "load on demand". I override OnBeforeExpand() so as you expand a node it updates the text/imageindex of the children which works really well. The number of node children is usually around the 10-20 mark but often only a few, so very little processing involved this way. Performance is great under 1.1. However running exactly the same code under .Net 2.0 gives what ranges from "appalling" to just plain "dire" usability. The "improved" performance is gained by adding BeginUpdate/EndUpdate around the code which iterates through the child nodes updating the .Text. However the performance is still completely awful compared to .Net 1.1, and it comes down to the .EndUpdate method which is chewing up the time in it's calls to Control.SendMessage. The alternative without using BeginUpdate/EndUpdate? I found that when setting the Node.Text property the TreeView goes into meltdown with literally millions of windows messages and handle requests initiated through TreeNode.set_Text -> TreeNode.UpdateNode -> TreeView.ForceScrollbarUpdate. As an experiment I set "Scrollable=false" on the TreeView. Sure enough, I now get the equivalent of .Net 1.1 performance when expanding... but of course now the treeview is not scrollable. You ask "why not just turn that off and on afterwards then"? Because the TreeView appears to completely reset and redraw itself when the Scrollable is set back to true which is completely unusable. So - I'm knackered if I used EndUpdate, and I'm knackered if I don't. Does anyone have any suggestions? At the moment it is "don't use .Net 2.0" which clearly ain't gonna fly long term. Many thanks. Tag: CallWindowProc NullReferenceException -- ParkingWindow Tag: 105081
  - 24
    - Launching and controlling MS ACCESS through my windows form I am trying to open a MS Access Front end through my windows form app. It opens fine when the file doesn't need a password. System.Diagnostics.Process.Start("C:\DBFrontEnds\Employee.mdb") Is there a way I can pass the password to Access in this case? I have looked into the startprocessInfo but I am not sure if thats the right direction to head in. Any help or suggestions are much appreciated. Also if this is something that is not possible is there a way to terminate any MS Access application running on the machine so that I could then delete the file? Tag: CallWindowProc NullReferenceException -- ParkingWindow Tag: 105076
  - 25
    - I really, really need smtp help I am trying to get some help on how to send email via a remote smtp server. I have posted here several times already. I need to be able to send email using winforms, vb.net 2003 or 2005 through a remote smtp server. The server is hosted by Web.com and I have talked to them but their support is NO HELP at all. I keep getting the error: Could not access 'CDO.Message' object Here is the code that I am using: Public Sub sendEmail(ByVal hostname As String) Dim objMail As New MailMessage Try objMail.To = "address@to.com" objMail.From = "address@from.com" objMail.Subject = "Testing" objMail.Body = "Body" objMail.Fields.Add("http://schemas.microsoft.com/cdo/configuration/smtpserver", "smtp.registeredsite.com") 'basic authentication objMail.Fields.Add("http://schemas.microsoft.com/cdo/configuration/smtpserverport", 25) 'basic authentication objMail.Fields.Add("http://schemas.microsoft.com/cdo/configuration/smtpauthenticate", 1) 'basic authentication objMail.Fields.Add("http://schemas.microsoft.com/cdo/configuration/sendusing", 2) 'basic authentication objMail.Fields.Add("http://schemas.microsoft.com/cdo/configuration/sendusername", "myusername") 'set your username here objMail.Fields.Add("http://schemas.microsoft.com/cdo/configuration/sendpassword", "password") 'set your password here SmtpMail.Send(objMail) Catch ex As Exception Throw ex End Try End Sub I really need help on this so that I can finish this project. -- Thanks, enak Tag: CallWindowProc NullReferenceException -- ParkingWindow Tag: 105073
- Next
  - 1
    - MDI Child jiggles like a bowl full of jelly. One of my continuing series of postings explaining why VSTS 2005 is not ready for prime time and asking for help. Create a mdi parent form. Add ToolStripPanels to all four sides. Put a flow control menustrip in the top panel and a toolstrip below it. All very reasonable things to do. Now create a child form and set its initial state to maximized. (The customer wants it that way.) Add it to the parent and show. The child gets the chills and jiggles in size like a bowl full of jelly. With apologies toi Clement Moore this is not a laughing matter. Suggestions please. -- Regards, Al Christoph Senior Consultant Three Bears Software, LLC just right software @ just right prices @ 3bears.biz Microsoft Certified Partner (ISV) Coming soon: Windows Mail for Vista. Tag: CallWindowProc NullReferenceException -- ParkingWindow Tag: 105070
  - 2
    - Controls.Add changes .Visible Visual Studio 2005 (Ver 8.0.50727.42) / Framework 2.0.50727 / XP Pro SP2 Given a Form, A, and another Form, B, that derives from A. Form A has 4 controls on it. When A.InitializeComponent (a compiler-generated method) executes, those 4 controls are added to A's Controls collection thusly: this.Controls.Add(this.Control1); The problem... Immediately prior to the above statement the control's Visible property is True; immediately after the statement the control's Visible property is False. Why? When similar statements are executed for Form B the Visible property is not changed on its controls. -- // Lee Silver // Information Concepts Inc. Tag: CallWindowProc NullReferenceException -- ParkingWindow Tag: 105069
  - 3
    - KeyDown messages lost with .NET message loop Hi, We're developing an application that has some .NET and some MFC components. Currently the application is started as an MFC application, but using a managed message loop (invoking Application::Run() in MFC's application class). With this configuration we experience some problems with keyboard messages. For example, some WM_KEYDOWN messages (for example for arrow keys) does not make it through to the MFC window class. I've registered a message filter to the Application class and I can see the message being received with the correct HWND handle. For some reason, this message is later lost and is not received by the WindowProc() method of the MFC window class. Interestingly, all simple keys (letters) are received correctly. Does anybody has any idea what is going on here? (We've thought using the MFC message loop, but MS docs suggest using a managed loop if .NET components are used). Genady Beryozkin, Algotec Systems. Tag: CallWindowProc NullReferenceException -- ParkingWindow Tag: 105068
  - 4
    - Field is never assigned to, and will always have its default value private struct MySTRUCT { public IntPtr hwndMyObj; public Int32 idMyObj; public Int32 MyCode; } In Vb.Net 2005 code above, I am getting a warning message "MyProj.MyClass.MySTRUCT.hwndMyObj is never assigned to,and will always have its default value." The same message for idMyObj and MyCode. How do I resolve it? Tag: CallWindowProc NullReferenceException -- ParkingWindow Tag: 105061
  - 5
    - Textbox with blinking cursor does not receive key input In our Windows Forms app we are having an issue that our login dialog (a System.Windows.Forms.Form) does not always receive focus. In this case the cursor blinks in the textbox however the field does not receive any key inputs and therefore does not display any text entered. The user needs to click manually in the textbox which is obviously not the ideal option. I would appreciate any suggestions on this topic. huli Tag: CallWindowProc NullReferenceException -- ParkingWindow Tag: 105054
  - 6
    - Log in I need to write two forms, frmMain and frmLogin. I would like to show frmMain after i pres a button in frmLogin. any ideas ? tnx Tag: CallWindowProc NullReferenceException -- ParkingWindow Tag: 105051
  - 7
    - Bug with ComboBox selection? I'm having a problem with the .NET ComboBox control and I was wondering if this is a bug, or if there is a workaround. When I programmatically select an index in the combobox, the correct index isn't selected when the combobox is expanded I have a WinForm and I've added a ComboBox and a push button control. In the Form's Load method, I have the following: private void Form1_Load(object sender, EventArgs e) { this.comboBox1.Items.Add("bbb"); this.comboBox1.Items.Add("ccc"); this.comboBox1.Items.Add("aaa"); } // I should point out that the combo box is unsorted. private void button1_Click(object sender, EventArgs e) { int nIndex; nIndex = this.comboBox1.Items.Add("cc"); // at this point, the text displayed by the combobox is // "cc" and nIndex is 3 (correct, as expected) this.comboBox1.SelectedIndex = nIndex; // at this point, comboBox.SelectedIndex is 3 (correct) and // comboBox.SelectedItem is "cc" (also correct), yet when I // continue and then click on the drop-down button, "ccc" is // selected // this also reveals the bug //nIndex = this.comboBox1.FindStringExact("cc"); //this.comboBox1.SelectedIndex = nIndex; } Am I doing something wrong? If not, does anyone know of a workaround? Thanks, JB Tag: CallWindowProc NullReferenceException -- ParkingWindow Tag: 105044
  - 8
    - C# Wanna BE Hi i have a url that if i paset it into IE it returns to me a zip file from a remote server. it asks me where do i want to save it then creates the zip file. the file contains the data that i have requested I have created a desk top app that makes the same request to the same remote server using and HTTPrequest when i get the response back. how i write a zip file to my c Drive but it contains 0 bytes. how do i extract the Zip file from my web response and save it to my computer. thanks. Tag: CallWindowProc NullReferenceException -- ParkingWindow Tag: 105043
  - 9
    - Combobox droppeddown property and strange mouse cursor behaviour Hello, When I set the droppeddown property of a combobox in my form load procedure, it sets the mouse cursor to the hourglass for the whole form - but I'm not sure why. I would like it to keep the default mouse pointer but when I set the droppeddown property it changes the cursor and it won't change back until I select something from the combobox. Even weirder is that if I keep my mouse cursor over the place where the form will eventually appear, the cursors behave properly. It only changes to the wait cursor if my mouse cursor is outside of the application form as it loads. For a quick example make a form with a single combobox and then: Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load ComboBox1.DroppedDown = True End Sub If you run this form with your mouse cursor far away from where the form will load - you should see that the cursor for the whole form is an hourglass. Does anyone know why this might be happening and what I could do to make it behave 'properly'? Thanks a lot - Cam Epp Tag: CallWindowProc NullReferenceException -- ParkingWindow Tag: 105039
  - 10
    - Assign Combined FontStyle on the fly Hi all, I know for fontStyle, I can specify FlagAttribute to get a combone FontStyle like so FontStyle.Bold | FontStyle.Underline The problem I'm having is, depending on what users clicked, I need to dynamically concate the FontStyle together. How do I do that? FontStyle fontstyle; if (Bold.Checked) { } if (UnderLine.Checked) { } If (Italic.Checked) { } Font myFont = new Font (.... , fontstyle, ) Thanks a lot. Tag: CallWindowProc NullReferenceException -- ParkingWindow Tag: 105038
  - 11
    - Resizable winform Hi there I'm using .NET 2.0. When I have a winform with controls how do I make it resizable ? I have tried each of the LayoutManagers that stick with Visual Studio 2005, but they do not look like they have the desired funtionality... Thanks in regards, Jess Tag: CallWindowProc NullReferenceException -- ParkingWindow Tag: 105035
  - 12
    - Unable to edit/move/remove controls in Subclassed form Hi, I am subclassing a Form and cannot edit, move or remove controls - or change their properties. A little lock appears by each control. This is in VS2005. How can I control what can be done to subforms, for instance if I were to give my forms to someone and let them derive subclasses and modify them in a controled way? -- Thanks in advance, Juan Dent, M.Sc. Tag: CallWindowProc NullReferenceException -- ParkingWindow Tag: 105034
  - 13
    - mousemove not getting to event handler we have an application in C# in which MouseMove is not behaving as expected. We have a form which has a TreeView, and the TreeView has a ContextMenu assigned to it (which is set to AutoClose). We have an MDI Child window that has a PictureBox on it. Mouse Event handlers are hooked to methods when the child window becomes the active window. We have a ToolStrip and ToolStripButtons, one of which when pressed adds an event handler to the PictureBox's MouseMove event (and several others). Normally, when the ToolStripButton is pressed a propery of the active window is set. When the mouse is moved into the picturebox the event handler is fired. If the user brings up the context menu and dismisses it by choosing one of the entries, and then clicks the ToolStripButton, the application works as expected. However, if the user brings up the context menu on the TreeView and then clicks directly on the ToolStripButton, and then moves the mouse into the PictureBox, the event handler for the mouse move is never called. Other mouse event handlers (such as MouseDown and MouseUp) will get called. Eventually, the problem becomes persistent enough that closing the application and restarting it is not enough to "fix" it. Windows has to be restarted. The "work around" we have found is to bring up the context menu and then click one of the options, and then the mouse move messages will be sent to the PictureBox as expected. Tag: CallWindowProc NullReferenceException -- ParkingWindow Tag: 105031
  - 14
    - Past due query I am trying to create a past due query of active quotes but instead of giving me a sum, it gives me multiple sums all equal to 1. I assume it is due to the "group by" being different but it won't let me do the query without it. What am I doing wrong? SELECT COUNT(QuoteDueDate) AS Expr1 FROM Quotes GROUP BY QuoteDueDate HAVING (QuoteDueDate < @Date) Tag: CallWindowProc NullReferenceException -- ParkingWindow Tag: 105029
  - 15
    - System.UnauthorizedAccessException Access to the path "Filename" is denied. Hi All, I have a windows Application in vb.net. I have a file copy function the program copies a file from a network share to a temp directory on the local machine then launchs this file from the Temp directory. When the program executes it raises the above exception when copying the file. Everyone has full control of the network share. Public Function ViewFileRecord(ByVal sGuid As String) PropProperties(sGuid) Try If File.Exists(sPathTarget) Then File.Delete(sPathTarget) End If File.Copy(sPathSource, sPathTarget, True) AttachProgTypes(sExtnFile) Exit Function Catch eFile As FieldAccessException ExceptionMessage(eFile) End Try End Function Any body any ideas. Thanks, Pete. Tag: CallWindowProc NullReferenceException -- ParkingWindow Tag: 105026
  - 16
    - Dowload File Hi, I have problem with downloading a file using WebRequest and HttpWebResponse. Inorder to download this file i need to call to url that tells to prepare the file for download, and then i call to another url that downloads the file. I have a problem with that because: 1. i do not know when the server finished the preparetion. 2.i checked the HttpStatusCode but he doen't changes (myresponse.StatusCode). the problem causes the application to download only a part of the file and that because the server hasn't prepared the file yet. if i give him Thread.Sleep(100000) i do get the full file, but the file can be 100Mb and 10sec won't help. the code is: //Preparing the file todownload... //--------------------------------------------------------------------------------------------------------- HttpWebRequest webRequest3 = WebRequest.Create(d1) as HttpWebRequest; webRequest3.KeepAlive = true; webRequest3.Headers.Add("Keep-Alive", "300"); webRequest3.Headers.Add("Accept","text/xml,application/xml,application/xhtml+xml,text/html;q=0.9,text/plain;q=0.8,image/png,*/*;q=0.5"); webRequest3.Headers.Add("Accept-Language", "en-us,en;q=0.5"); webRequest3.Headers.Add("Accept-Encoding", "gzip,deflate"); webRequest3.Headers.Add("Accept-Charset", "ISO-8859-1,utf-8;q=0.7,*;q=0.7"); webRequest3.CookieContainer = cookies; HttpWebResponse myResponse3 = (HttpWebResponse)webRequest3.GetResponse(); Thread.Sleep(10000); Stream ReceiveStream3 = myResponse3.GetResponseStream(); //----------------------------------------------------------------------------------- //Downloading .... //-------------------------------------------------------------------------------------- Console.WriteLine("Connecting to download link..."); HttpWebRequest webRequest2 = WebRequest.Create(re) as HttpWebRequest; webRequest2.ContentType = "application/x-www-form-urlencoded"; webRequest2.KeepAlive = true; webRequest2.CookieContainer = cookies; HttpWebResponse myResponse2 = (HttpWebResponse)webRequest2.GetResponse(); Stream ReceiveStream2 = myResponse2.GetResponseStream(); Console.WriteLine("Downloading..."); Common.SaveStreamToFile(@"C:\scrapingtest\file.csv", ReceiveStream2); Console.WriteLine("Done Downloading"); Thanks, Rony Tag: CallWindowProc NullReferenceException -- ParkingWindow Tag: 105012
  - 17
    - How to display unicode characters using a special codepage. hello all, Using framework 2.0 I have to display a text, given as a xml data file. The given text contains extended unicode data (see below 'â??' represents arrow up decimal code # 8593 given as direct unicode # 2191) <?xml version="1.0" encoding="iso-8859-1" ?> <help> <display>&x2191 ;</display> </help> The codepage for iso-8859-1 is WindowsCodePage 28591 which is mapped to codepage Windows-1252. No culture settings displays the right sign on my DotNet Form. The TextInfo properties are readonly. How is it possible to display unicode characters from changing encodings on my form. Tag: CallWindowProc NullReferenceException -- ParkingWindow Tag: 105011
  - 18
    - Maximum size of a form created using VB .NET 2005 Is there a limitation with the .NET 2005 VB form designer that prevents a designer from creating a window larger than 2972(w), 1062(h) pixels and if so, is there a way I can get around the limitation? I need to design forms having the same size as my screens 1600x1200 and 1200x1600, and am not having any luck; even setting the value at runtime rather than as a property of the designer. Does anyone have any suggestions? Thanks. Tag: CallWindowProc NullReferenceException -- ParkingWindow Tag: 105009
  - 19
    - System.net.Mail class a html images I'm trying to send html mails from my .net app and I have problem putting an image file in mail body without putting it into attached files. How can I do? Thks Tag: CallWindowProc NullReferenceException -- ParkingWindow Tag: 105003
  - 20
    - ListControl/DataGridView/PropertyGrid Ellipses...how to? In Visual Studio, if you select Tools->Options then expand the Projects and Solutions node, and select VC++ directories, you get a grid like (or list box like) form that allows you to type in directories. If you double click on a line, you get an ellipsis that displays the directory dialog browser. Is this implemented with a data grid and two columns, and the ellipsis is hidden until there's a double click? A list box? A property Grid? There's not much documentation on ellipses, so I gather it's not part of a standard MSFT control. I haven't found many *recent* messages on the topic in these groups. I want to emulate this behavior for an app (although I'll be selecting files, not directories). The place I work for also has Infragistics controls...I may be able to get something from there, but they're tough to use. I'd rather go with something from MSFT if I could. I'll be using C#, but that doesn't make much difference, as long as it's dotnet, it should work. Thanks, Jeff Tag: CallWindowProc NullReferenceException -- ParkingWindow Tag: 105002
  - 21
    - RTL Treeview Control Problem Hi, i'm having a problem with RTL Treeview to enable Mapping Trees with Left and Right TreeView. On the right-hand side is a Right-To-Left TreeControl showing up some nodes. Between the left tree and the right tree there are some connection lines. And now comes my problem: everything is working fine on the natural box. But if i'm switching to remote desktop the connection lines on the RTL Trees are incorrect painted by Graphics.DrawLine(). Realy curious. (wrong direction!) Ideas, suggestion,.. are welcome. Greetings, Ralf Tag: CallWindowProc NullReferenceException -- ParkingWindow Tag: 105000
  - 22
    - Controls of a form Hello I have a form that containes a lot of controls including panels those contain other controls. Is there a way to simply get all contained controls either directly or indirectly through other containers such as panel or GroupBox controls? Tag: CallWindowProc NullReferenceException -- ParkingWindow Tag: 104999
  - 23
    - How to trap Application Form Change event? Hello, I had to disabled Form Inheritance because bug in VS 2005 in inheritance and localization. ANy suggestion how to trap form when it is to display or something simmiliar, in order to set common properties for all forms. For example: (Not to show in taskbar) thanks MilanB Tag: CallWindowProc NullReferenceException -- ParkingWindow Tag: 104998
  - 24
    - A little help on understanding properties ?? Hi, I'm currently working on an scenegraph editor. I have a treeview, and when I select a node, it shows its properties in a propertygrid. Each node has a link to the scenegraph node, and I override the property accessors to modify the scenegraph node when the user change something in the propertygrid. For example : // this is a custom 3 dimensional vector object. [TypeConverterAttribute(ExpandableObjectConverter::typeid)] public ref struct CVector3 { CVector3(void) { x = 0.0f; y = 0.0f; z = 0.0f; } CVector3(float X, float Y, float Z) { x =X; y = Y; z = Z; } property float x; property float y; property float z; virtual String ^ ToString(void) override { return("" + x + "; " + y + "; " + z); } }; Now, in the treeviewnode, I have something like : property CVector3 ^ Position { void set(CVector3 ^ value) { // when the Position property is modified, I want // to send the new position to the scenegraph node. m_pNode->SetPosition(value->x, value->y, value->z); } CVector3 ^ get(void) { // I always get the position from the scengraph node. return(gcnew CVector3(m_pNode->GetPositionX(), m_pNode->GetPositionY(), m_pNode->GetPositionZ()); } } where m_pNode is a pointer to the associated scenegraph node. Now, the problem is that when I expand the Position property, and modify the x component, the CTreeViewNode::Position::set() method is not called. I overrided the x, y and z accessors in the CVector3, and they are correctly called, but I need to "notify" my CTreeViewNode that its Position property changed, and I really don't know how to do that :/ If anyone know how to do this, I would really appreciate a little help ^^ And I apologize for my english :/ If you didn't understand my problem, tell me, I'll try to be a little clearer ^^ Have a good day. Damien Tag: CallWindowProc NullReferenceException -- ParkingWindow Tag: 104996
  - 25
    - Arrow keys work in opposite direction in panel Hi, I have a panel in my project (C# .NET 2003). I have multiple radio buttons placed in it. When I press UP Arrow key, The focus in the screen moves one radio button DOWN. ofcourse if I press DOWN Arrow key the focus in the screen will move one radio button UP. I guess this is because of the way the radio button controls are arranged in the panel control collection. Could anyone suggest a way to override this behaviour in a way that when pressing UP Arrow key the focus in the screen will move one radio button UP and so on... TIA Kuchuk Tag: CallWindowProc NullReferenceException -- ParkingWindow Tag: 104995

[System.NullReferenceException]

Message: Object reference not set to an instance of an object.

at System.Windows.Forms.UnsafeNativeMethods.CallWindowProc(IntPtr
wndProc, IntPtr hWnd, Int32 msg, IntPtr wParam, IntPtr lParam)
at System.Windows.Forms.NativeWindow.DefWndProc(Message& m)
at System.Windows.Forms.Control.DefWndProc(Message& m)
at System.Windows.Forms.Control.WmUpdateUIState(Message& m)
at System.Windows.Forms.Control.WndProc(Message& m)
at System.Windows.Forms.ScrollableControl.WndProc(Message& m)
at System.Windows.Forms.ContainerControl.WndProc(Message& m)
at System.Windows.Forms.ParkingWindow.WndProc(Message& m)
at System.Windows.Forms.ControlNativeWindow.OnMessage(Message& m)
at System.Windows.Forms.ControlNativeWindow.WndProc(Message& m)
at System.Windows.Forms.NativeWindow.Callback(IntPtr hWnd, Int32
msg, IntPtr wparam, IntPtr lparam)

When pressing various buttons in our application (that open or close
forms), we randomly (infrequently) receive the above stack trace.

I see lots of posts on this topic but very few answers -- it seems that
we can 1) subclass the standard .NET controls or 2) upgrade to .NET
2.0.

What about 1.1? If it is fixed in 2.0, is there not a hotfix available
in 1.1? I searched the Microsoft KB but have not had any luck yet.

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