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DOEVENTS Command

Executes all pending Windows events.

Note   You can no longer call DOEVENTS using parentheses (()), for example, DOEVENTS( ).

You can use DOEVENTS for simple tasks such as making it possible for the user to cancel a process after it starts, for example, searching for a file. Long-running processes that yield control of the processor are better performed using a Timer control or delegating the task to an ActiveX executable (.exe) component. In this situation, the task can continue independently of your application, and the operating system takes care of multitasking and time allocation.

Caution   Any time you temporarily yield control of the processor in an event procedure, make sure the procedure is not run again from a different part of code before the first call ends. Doing so might cause unpredictable results. In addition, do not use DOEVENTS if other applications might interact with your procedure in unforeseen ways during the time you have yielded control of the processor.

DOEVENTS [FORCE]

Parameters

  • FORCE
    Pauses Visual FoxPro code execution until a Windows event occurs, such as moving the mouse.

    Note   Using the FORCE keyword can impact performance. Therefore, use caution when calling DOEVENTS FORCE in a tight code loop, such as a DO WHILE loop.

Remarks

When the AutoYield property is set to False (.F.), and program code is executing, Window events are placed in a queue. DOEVENTS executes all pending Windows events and processes any user code associated with the Windows events. If no events are in the queue, Visual FoxPro disregards DOEVENTS and continues program execution.

See Also

AutoYield Property | Events