Microsoft KB Archive/202019

= WD2000: Converted WordBasic On Error Statements May Fail =

Article ID: 202019

Article Last Modified on 6/17/2005

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APPLIES TO


 * Microsoft Word 2000 Standard Edition

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This article was previously published under Q202019





SYMPTOMS
When you run a Microsoft Visual Basic for Applications procedure or macro that was converted from a WordBasic procedure or macro that contained error trapping, the error trap is ignored, although it worked as expected when run in WordBasic.



CAUSE
Microsoft 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.

By design, the On Error statement in Visual Basic for Applications works differently from the way it does in WordBasic. In Visual Basic for Applications, On Error is not cleared when an error occurs. In WordBasic, the On Error statement is cleared, the error trap is reset, and your code continues to run.

Therefore, the following sample converted WordBasic code fails when an error occurs the second time.

Sub Main ' Clear error trap. Set error trap. On Error GoTo -1: On Error GoTo ErrorTrap ' Loop 10 times. For i = 1 To 10 ' Artificially raise an error. Err.Raise 5 ErrorTrap: ' Decision tree based on error returned. If Err.Number = 0 Then ' If no error occurred, do this... count_ = count_ + 1 Else ' Else, if error occurred, do this... Err.Number = 0 End If  Next End Sub



WORKAROUND
To work around this issue, make the On Error statement the first statement inside the loop.

Sub Main ' Loop 10 times. For i = 1 To 10 ' Clear error trap. Set error trap. On Error GoTo -1: On Error GoTo ErrorTrap ' Artificially raise an error. Err.Raise 5 ErrorTrap: ' Decision tree based on error returned. If Err.Number = 0 Then ' If no error occurred, do this... count_ = count_ + 1 Else ' Else if error occurred, do this... Err.Number = 0 End If  Next End Sub

In this example, the Err.Raise statement artificially raises an error for demonstration purposes. When the error occurs and the next iteration of the loop occurs, the On Error GoTo -1 statement clears the error trap and the On Error GoTo ErrorTrap statement resets the error trap. The loop continues to process without interruption until it completes the designated number of iterations (10).



STATUS
Microsoft has confirmed that this is a problem in the Microsoft products that are listed at the beginning of this article.

