FIX: App.End in the Form Load Event Causes Application Error

ID: Q180520

The information in this article applies to:

SYMPTOMS

If the App.End method is used in the Form Load event, it will cause the following application error in PVB.EXE on the emulator:

The instruction at "0x0135baa1" referenced memory at "0x00000000". The memory could not be "read".
On the device, a message box with the title "Fatal Application Error" will appear and automatically go away before it can be read.


RESOLUTION

There two possible workarounds for this bug:

  1. Use a timer to invoke the App.End method. Simply placing App.End in the Timer Event and enabling the Timer at the desired time would end the application.


  2. Set a flag during the Form Load event and, when the Form Activate event is called, check the flag and end the application if the flag has been set. Add the following code to a form to demonstrate this: 
    
      Option Explicit
      Dim bEndAppFlag

      Private Sub Form_Activate()
          If bEndAppFlag Then App.End
      End Sub

      Private Sub Form_Load()
          On Error Resume Next
          'Simulate an error
          Err.Raise 53

          If Err.Number <> 0 Then
              'An error occurred during form load,
              'so exit the app by setting our flag.
              bEndAppFlag = True
          End If
     End Sub



STATUS

Microsoft has confirmed this to be a problem in the Microsoft products listed at the beginning of this article.

This problem was corrected in Windows CE Toolkit for Visual Basic 6.0.


MORE INFORMATION

Steps to Reproduce Behavior

WARNING: The following code will generate a fatal application error.
  1. Create a new Windows CE project in Visual Basic 5.0. Form1 is created by default.


  2. Add the following code to the Form Load event: 
    
      Private Sub Form_Load()
          'WARNING: Generates a fatal application error.
          App.End
      End Sub


  3. Press the F5 key to run the project.


© Microsoft Corporation 1999, All Rights Reserved.
Contributions by Mike Dixon, Microsoft Corporation

Additional query words: wince vbce vbce5 vbce6 


Keywords          : kbToolkit kbVBp kbVBp500bug kbVBp600fix kbWinCE kbWinCE100 kbGrpVB 
Version           : WINDOWS:1.0
Platform          : WINDOWS 
Issue type        : kbbug

Last Reviewed: February 25, 1999