Breakpoint in LostFocus Event Procedure Can Hang VB.EXE

ID Number: Q77927

1.00

WINDOWS

buglist1.00

Summary:

Placing a breakpoint in a control's LostFocus event procedure can

cause the VB.EXE environment to hang under the following conditions:

- If there is also a breakpoint in an event procedure for a second

control that will be executed when the focus is transferred from

the first control (with the breakpoint in its LostFocus event) to

the second control

- If you transfer focus from the first control to the second control

and continue executing the program after encountering the

breakpoint in the second control's code

VB.EXE may also hang if you have a breakpoint in the event that

executes for the control receiving focus, and you are stepping through

the code (by pressing F8).

Microsoft has confirmed this to be a problem with Microsoft Visual

Basic programming system 1.0 for Windows. We are researching the

problem and will post new information here as it becomes available.

More Information:

Steps to Reproduce Problem

--------------------------

1. Start Visual Basic (or choose New Project from the File menu).

2. Create two command buttons, Command1 and Command2, on Form1.

3. Add the following code to the LostFocus event for Command1:

Sub Command1_LostFocus

x = 1

End Sub

4. Place the cursor on the statement "x = 1," and press F9 to place a

breakpoint.

5. Add the following code to the Click event procedure for Command2:

Sub Command2_Click

x = 1

End Sub

6. Place a breakpoint on the "x = 1" line in Command2_Click.

7. Press F5 to execute the program. Click on Command2; this should stop

the program at the breakpoint in Command2_Click. Press F5 to

continue; the Visual Basic title bar will flash, the cursor will

change to an hour glass, and the system will be locked, requiring a

reboot.

Additional reference words: 1.00