FIX: Button Parameter of DataGrid MouseUp Event Always Equals 0

• Microsoft Visual Basic Professional and Enterprise Editions for Windows, version 6.0

SYMPTOMS

Using the MouseUp and MouseDown events of the DataGrid control, you see the following symptoms:

• The Button argument of the DataGrid MouseUp event is 0, regardless of which mouse button is used.



• When two mouse buttons are pressed together, the Button argument of the DataGrid MouseDown event is 3 and the Button argument is incorrect for the MouseUp event.

RESOLUTION

This behavior no longer occurs with the version of the DataGrid that ships with Visual Basic 6.0 Service Pack 3.

STATUS

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

This bug was corrected in Visual Studio 6.0 Service Pack 3. For more information about Visual Studio service packs, please see the following articles in the Microsoft Knowledge Base:

Q194022 INFO: Visual Studio 6.0 Service Packs, What, Where, Why

Q194295 HOWTO: Tell That Visual Studio 6.0 Service Packs Are Installed

MORE INFORMATION

The MouseDown event occurs when a mouse button is pressed over an object.

The MouseUp event is raised when a mouse button is released over an object.

The MouseMove event occurs when the mouse is moved over an object.

The Button argument is an integer that indicates which mouse button was used during a MouseDown, MouseUp, or MouseMove event.

The Button argument should be 0 if no button is used, 1 if the left button is used, 2 if the right button is used, or 4 if a middle button is used.

While the Button argument may be incorrect for the DataGrid MouseUp and MouseDown events, the Button argument is correct for the DataGrid's MouseMove event.

Steps to Reproduce Behavior

1. In Microsoft Visual Basic 6.0, create a new standard EXE project. Form1 is created by default.



2. From the Project menu, choose Components. Select the Microsoft DataGrid Control 6.0 (OLEDB) and then click OK.



3. Add a DataGrid to the Form1. DataGrid1 is created by default.



4. Paste the following code into the code window for Form1:




   Private Sub DataGrid1_MouseUp(Button As Integer, Shift As Integer, X As    Single, Y As Single)
      Debug.Print "DataGrid1_MouseUp:" & Button
   End Sub

   Private Sub DataGrid1_MouseDown(Button As Integer, Shift As Integer, X    As Single, Y As Single)
      Debug.Print "DataGrid1_MouseDown:" & Button
   End Sub

   Private Sub Form_MouseUp(Button As Integer, Shift As Integer, X As    Single, Y As Single)
      Debug.Print "Form_MouseUp:" & Button
   End Sub

   Private Sub Form_MouseDown(Button As Integer, Shift As Integer, X As    Single, Y As Single)
      Debug.Print "Form_MouseDown:" & Button
   End Sub 

5. Before running the project, open the View menu, and select Immediate Window. The Immediate Window allows you to see the output of the Debug.Print statements at run-time (and later, back in design mode).



6. Run the project.



7. Position the mouse pointer over the Form, but not over the DataGrid.
   Perform the following sequence of mouse operations:



1. Press (and hold) the left mouse button.



2. Press (and hold) the right mouse button.



3. Release the left mouse button.



4. Release the right mouse button.





You will see the following sequence in the Immediate Window:


• Form_MouseDown: 1
• Form_MouseDown: 2
• Form_MouseUp: 1
• Form_MouseUP: 2


NOTE: These are the correct mouse Button values.


8. Position the mouse pointer over the DataGrid. Perform the following sequence of mouse operations:



1. Press (and hold) the left mouse button.



2. Press (and hold) the right mouse button.



3. Release the left mouse button.



4. Release the right mouse button.





You will see the following sequence in the Immediate Window:

• DataGrid1_MouseDown: 1
• DataGrid1_MouseDown: 3
• DataGrid1_MouseUp: 2
• DataGrid1_MouseUP: 0



NOTE: These are not the correct mouse Button values. The correct sequence follows:

• DataGrid1_MouseDown: 1
• DataGrid1_MouseDown: 2
• DataGrid1_MouseUp: 1
• DataGrid1_MouseUP: 2

Additional query words:

Keywords : kbservicepack kbVS600sp2 kbVS600SP1 kbVS600sp3fix
Version : WINDOWS:6.0
Platform : WINDOWS
Issue type : kbbug