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Q160161: FIX: SPACE BAR+ARROW KEY Causes GPF When Unloading Form

Article: Q160161
Product(s): Microsoft Visual Basic for Windows
Version(s): WINDOWS:4.0
Operating System(s): 
Keyword(s): kbGrpDSVB
Last Modified: 11-JAN-2001

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The information in this article applies to:

- Microsoft Visual Basic Standard Edition, 32-bit, for Windows, version 4.0 
- Microsoft Visual Basic Professional Edition, 16-bit, for Windows, version 4.0 
- Microsoft Visual Basic Professional Edition, 32-bit, for Windows, version 4.0 
- Microsoft Visual Basic Enterprise Edition, 16-bit, for Windows, version 4.0 
- Microsoft Visual Basic Enterprise Edition, 32-bit, for Windows, version 4.0 
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SYMPTOMS
========

With a form that contains at least two controls that are capable of receiving
focus, if the SPACE BAR+ARROW KEY combination is pressed while the focus is on
the control whose click event contains the code "Unload Me," a General
Protection Fault (GPF) will occur.

RESOLUTION
==========

Instead of unloading the form immediately in the click event of a control, place
a Timer control on the form and use it to defer this action for one millisecond
using the following code:

     Private Sub Command1_Click()
         '''Unload Me
         Timer1.Interval = 1
     End Sub

     Private Sub Timer1_Timer()
         Unload Me
     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 Problem
--------------------------

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

2. Place two CommandButtons, Command1 and Command2, on Form1.

3. Place the following code in the Command1_Click event:

     Private Sub Command1_Click()
         Unload Me
     End Sub

4. Run the project by pressing the F5 key.

5. With the focus on Command1, press the SPACE BAR+ARROW KEY combination and
  note that a GFP occurs.

Additional query words: kbVBp400bug kbVBp600fix kbVBp kbdsd kbDSupport kbCtrl

======================================================================
Keywords          : kbGrpDSVB 
Technology        : kbVBSearch kbAudDeveloper kbVB400Search kbVB400 kbVB16bitSearch
Version           : WINDOWS:4.0
Issue type        : kbbug
Solution Type     : kbfix

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