Creating time delays is often required in applications for various
reasons, e.g., flashing a message to the user by writing, say, 'All
Changes Saved...' to the StatusBar and deleting it after a couple of
seconds. There are several way to do this, but the simplest way is a
For..Next loop of a predetermined size. The only drawback with that method
is the
time delay is then dependent on processor speed. However a simple idea,
again employing a loop is to use the Timer property to determine the point
of exiting the loop. In the procedure below the required time delay is
passed into the procedure and the loop is executed until the Timer recognizes
the time delay has elapsed. In the event a large time delay is required, a
condition is added to yield so the operating system can process other
events in addition to the timer loop.
Public Sub Delay(sngSeconds As Single)
Dim timSnapShot As Single
Dim timYieldCheck As Single
timSnapShot = Timer
timYieldCheck = Timer
Do Until Timer > timSnapShot + (sngSeconds)
'yield to Windows every 10 seconds
If Timer > timYieldCheck + 10 Then
timYieldCheck = Timer
DoEvents
End If
Loop
End Sub
If only short time delays are required then consider using an API to
control the delay such as the Sleep API shown below. The only limitation
being the absence of any OS yield event.
Declare Sub Sleep Lib "kernel32" (ByVal dwMilliseconds As Long)
Public Sub WindowsSleep(sngSeconds As Single)
Dim lngMilliseconds As Long
lngMilliseconds = 1000& * CLng(sngSeconds)
Call Sleep(lngMilliseconds)
End Sub
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