Visual Basic Combo Control Receives Extra "Click" Event

ID: Q82255

The information in this article applies to:

Microsoft Windows operating system versions 3.1, 3.11

SUMMARY

When you run Visual Basic in Microsoft Windows version 3.1, double-clicking an item listed in a simple Combo control generates the following events:


   Combo(x)_Click
   Combo(x)_Click
   Combo(x)_DblClick

However, in Windows 3.0, the events that were generated through the same action were:


   Combo(x)_Click
   Combo(x)_DblClick

This means an extra mouse-button click event is processed and can cause unexpected results.

MORE INFORMATION

This is a case where Visual Basic 1.0 is relying on the order in which messages are processed. Visual Basic was designed to use the message order that Windows 3.0 provides. Because Windows 3.1 uses an extended message order to process a "click" event, there is an extra occurrence if the application is dependent upon message order.

This is not a design problem in Windows 3.1 because Windows is sending the correct messages. Visual Basic is just "expecting" the messages to come in a specific order.

Additional query words: 3.10 visual basic events click double 3.11

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