Q299615: BUG: KeyPress Event Behaves Differently in a Compiled Executable

Article: Q299615
Product(s): Microsoft Visual Basic for Windows
Version(s): 5.0,6.0
Operating System(s): 
Keyword(s): kbActivexEvents kbCompiler kbVBp kbVBp500bug kbVBp600bug kbForms kbIDEProject kbGrpDSVB
Last Modified: 18-JUN-2001

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The information in this article applies to:

- Microsoft Visual Basic Enterprise Edition for Windows, versions 5.0, 6.0 
- Microsoft Visual Basic Professional Edition for Windows, versions 5.0, 6.0 
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SYMPTOMS
========

After displaying a dialog box in the KeyDown event, the KeyPress event is not
raised when you run a project in the Integrated Development Environment (IDE).
However, if you build the project into an executable file, the KeyPress event is
raised. The behavior of the KeyPress event should be the same in a built
executable as it is in the development environment. This inconsistency is
observed with form and control keyboard events.

RESOLUTION
==========

To work around this problem, store and use the window handle of the form or
control that raises the KeyDown event to determine if the code in the KeyPress
event should be run.

STATUS
======

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

MORE INFORMATION
================

Steps to Reproduce the Behavior
-------------------------------

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

2. Add the following code to the General Declarations section of Form1:

  Option Explicit

  Dim hWndAW As Long

  Private Declare Function GetActiveWindow Lib "user32" () As Long

  Private Sub Form_KeyDown(KeyCode As Integer, Shift As Integer)
      ' Save the active window handle
      ' when the KeyDown event occurs.
      hWndAW = GetActiveWindow()
      MsgBox "KeyDown Event"
  End Sub

  Private Sub Form_KeyPress(KeyAscii As Integer)
      ' To work around the problem, only run the
      ' desired code if the object that raised the
      ' KeyDown event is still the active window.
  '    If hWndAW = GetActiveWindow() Then
          Form1.Caption = "KeyPress Event"
  '    End If
  End Sub

3. Press the F5 key to run the program.

4. Press the SPACEBAR. Notice that a message box indicates that the KeyDown
  event has been raised. Also notice that the caption of the form remains
  "Form1," which indicates that the KeyPress event has not been raised.

5. Dismiss the message box, and close the running instance of Form1.

6. From the File menu, click Make, and build Project1 into an executable file.

7. Run the built executable.

8. Press the SPACEBAR. Notice that a message box indicates that the KeyDown
  event has been raised. However, notice that the caption of the form has
  changed to "KeyPress Event," which indicates that the KeyPress event has been
  raised.

To examine the workaround, uncomment the If and End If statements in the
Form_KeyPress event, and build the project into an executable file. When you run
this executable and press the SPACEBAR, the caption of the form remains "Form1,"
which indicates that code in the KeyPress event has been bypassed.

Additional query words: InputBox Compile execute

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Keywords          : kbActivexEvents kbCompiler kbVBp kbVBp500bug kbVBp600bug kbForms kbIDEProject kbGrpDSVB _IK 
Technology        : kbVBSearch kbAudDeveloper kbZNotKeyword6 kbZNotKeyword2 kbVB500Search kbVB600Search kbVB500 kbVB600
Version           : :5.0,6.0
Issue type        : kbbug
Solution Type     : kbpending

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