FIX: Invalid Page Fault When Deleting Nodes in TreeView Control

• Microsoft Visual Basic Learning, Professional, and Enterprise Editions for Windows, version 5.0
• Microsoft Visual Studio versions 97, 97sp1, 97sp2, 97sp3

SYMPTOMS

While attempting to delete nodes from a TreeView control, you receive an Invalid Page Fault and your Visual Basic application is terminated.

CAUSE

This problem may occur when the user clicks on the TreeView control and this action causes an event procedure to run that attempts to delete nodes from the TreeView before the TreeView gets the focus.

RESOLUTION

To correct this problem, call the DoEvents function in the MouseDown event of the TreeView Control. For example:

   Private Sub TreeView1_MouseDown(Button As Integer, Shift As Integer, _
     x As Single, y As Single)
        DoEvents
   End Sub 

STATUS

Microsoft has confirmed this to be a bug in the Microsoft products listed at the beginning of this article. This bug has been fixed in Visual Basic 6.0.

MORE INFORMATION

Steps to Reproduce Behavior

1. Start a new Standard EXE project in Visual Basic. Form1 is created by default.



2. Click Components from the Project menu and check Microsoft Windows Common Controls 5.0.



3. Place a TreeView control and a TextBox control on Form1.



4. Copy the following code to the Code window of Form1:

   
         Private Sub Form_Load()
            TreeView1.Nodes.Add , , "A", "A"
         End Sub
   
         Private Sub Text1_LostFocus()
            TreeView1.Nodes.Clear
         End Sub
    




5. On the Run menu, click Start, or press the F5 key to start the program.



6. Click on the TextBox so that it has the focus.



7. Click on the "A" node in the TreeView control.
   
   On Windows 95 or Windows 98, you receive the following error:

   VB5 caused an invalid page fault in module COMCTL32.DLL at <address>.

   On Windows NT, you receive the following error:

   Exception: Stack overflow in VB5.EXE

   -or-

   The exception unknown software exception (0xc00000fd) occurred in the application at location <address>.

   NOTE: You may have to repeat steps 6 and 7 several times before seeing the problem.

Additional query words: application error crash gpf ipf page fault kbVBp500bug kbVBp
kbDSupport kbdsd kbAPI kbVBp600fix kbVS97sp1 kbVS97sp2 kbVS97sp3 kbControl

Keywords : kbGrpVB
Version :
Platform : WINDOWS
Issue type : kbbug