XL: Canceling OnTime Macro When Time Argument Is Volatile (121212)
The information in this article applies to:
- Microsoft Excel 97 for Windows
- Microsoft Excel for Windows 95
- Microsoft Excel for Windows 5.0
This article was previously published under Q121212 SYMPTOMS
In Visual Basic for Applications, canceling a recursive OnTime macro may be
difficult when the earliestTime argument is volatile (for example, if you
are using the current time).
WORKAROUNDMicrosoft provides programming examples for illustration only, without warranty either expressed or implied. This includes, but is not limited to, the implied warranties of merchantability or fitness for a particular purpose. This article assumes that you are familiar with the programming language that is being demonstrated and with the tools that are used to create and to debug procedures. Microsoft support engineers can help explain the functionality of a particular procedure, but they will not modify these examples to provide added functionality or construct procedures to meet your specific requirements.
In order to cancel an OnTime method, you must call another OnTime method to
set the schedule argument equal to False. However, note that this method
will not work if the time argument in the OnTime method is set with the Now
function.
To prepare the first OnTime method so you can cancel it later, create a
time variable and use this variable in both cases, as in the following
example:
- Enter the following macro code into a module sheet in a new workbook.
Dim TimeNow As Double
Dim TimeStop As Double
Dim TimeSet As Double
Sub RunMeFirst()
TimeNow = Now
TimeStop = TimeNow + TimeValue("00:00:59") 'this sets the time at
'which all macros will
'stop
TimeSet = TimeNow + TimeValue("00:00:15")
Set_OnTime
End Sub
Sub Set_OnTime()
Application.OnTime TimeSet, "TestMacro"
If TimeSet > TimeStop Then 'compare the time to stop with the time
'at which the TestMacro is scheduled to
'run
Application.OnTime TimeSet, "TestMacro", , False
End If
End Sub
Sub TestMacro()
ActiveCell.Value = 1
ActiveCell.Offset(1, 0).Select
TimeSet = TimeSet + TimeValue("00:00:15")
Set_OnTime
End Sub
- Activate Sheet1 in your workbook.
- Run the RunMeFirst macro.
The TimeStop variable is set to 59 seconds after you run the RunMeFirst
macro and the TimeSet variable is set to 15 seconds after you run the
RunMeFirst macro. Then, the Set_OnTime macro is called, which in-turn
checks to see if the TimeSet variable is greater than the TimeStop
variable. If it is, then all macros stop. If it is not, then the TestMacro
is called. The TestMacro will place a value of 1 in the active cell, select
the next cell down from the active cell, and then reset the TimeSet
variable to 15 seconds past its current value. The TestMacro then calls the
Set_OnTime macro.
REFERENCES
For more information about the OnTime function, choose the Search button in
Visual Basic Help and type:
Modification Type: | Minor | Last Reviewed: | 10/11/2006 |
---|
Keywords: | kbProgramming KB121212 |
---|
|