BUG: WebClass ProcessTag event fails to execute (279409)


The information in this article applies to:

  • Microsoft Visual Basic Learning Edition for Windows 6.0
  • Microsoft Visual Basic Professional Edition for Windows 6.0
  • Microsoft Visual Basic Enterprise Edition for Windows 6.0 SP4
This article was previously published under Q279409

SYMPTOMS

When you run a WebClass project from within Visual Basic 6.0 Service Pack 4, and there is more than one WebClass tag in a Web document, the WebClass ProcessTag events may fail to execute. This does not occur if you browse the Active Server Pages (ASP) page directly.

CAUSE

This problem occurs if the previous execution of the ProcessTag event did not change the value of the TagContents variable. If your ProcessTag event never sets or modifies the value of the TagContents variable, every other tag is skipped.

RESOLUTION

To resolve this problem, while you are developing the WebClass project from within Visual Basic, set or modify the value of the TagContents variable every time the ProcessTag event executes. To do this, add the following line at the beginning of your ProcessTag event: 
TagContents = TagContents
This line can be commented out or removed when the Web project is put into production, but it must be put back next time you run the WebClass project from within Visual Basic.

STATUS

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

MORE INFORMATION

Steps to Reproduce Behavior

  1. Use the following template to create a WebClass project:
    <html>
<head><title>ProcessTag Event Test</title></head>
<body>
<h1>ProcessTag Event Test</h1>
The following should show three lines:  One, abc & Three<br>
Instead, it shows these three lines:  One, Two & Three<br>
To fix this problem, uncomment the code:  TagContents = TagContents<hr>
<WC@ONE>One</WC@ONE><br>
<WC@TWO>Two</WC@TWO><br>
<WC@THREE>Three</WC@THREE><br>
</form>
</body>
</html>
  2. In the WebClass project, paste the following code:
    Private Sub TagTemplate_ProcessTag(ByVal TagName As String, _
        TagContents As String, SendTags As Boolean)
    
    'Uncomment the following line to correct the problem.
    'TagContents = TagContents
    
    Select Case TagName
    Case "WC@ONE"
        'Do some work
    Case "WC@TWO"
        'Do some work
        TagContents = "abc"
    Case "WC@THREE"
        'Do some work
    Case Else
        'Do some work
    End Select
End Sub

Private Sub TagTemplate_Respond()
    TagTemplate.WriteTemplate
End Sub

Private Sub WebClass_Start()
    Set NextItem = TagTemplate
End Sub
  3. After you uncomment the following line of code: 
    TagContents = TagContents
    you must refresh the page in the browser to see the change.
For more detailed information on how to create a WebClass project in Visual Basic, see our sample projects at the following Microsoft Developer Network (MSDN) Web sites:

WCDemo Sample Project
http://msdn.microsoft.com/library/devprods/vs6/vbasic/vb98/vbsmpwebclassdemoapplication(wcdemovbp)professionalenterpriseedition.htm

Support1 Sample Project
http://msdn.microsoft.com/library/devprods/vs6/vbasic/vb98/vbsmpsupportapplicationprofessionalenterpriseeditions.htm

Support1 WebClass Tutorial
http://msdn.microsoft.com/library/devprods/vs6/vbasic/vbcon98/vbhowCreatingaWebclass.htm

REFERENCES

For additional information, click the article numbers below to view the articles in the Microsoft Knowledge Base:

192035 PRB: Do Not Use a WebClass ProcessTag Inside an HTML Tag

234317 FIX: HTML Page Truncated with Visual Studio SP3 WebClass Run Time when Running in the VB IDE

For more information on sample Visual Basic projects, see the following MSDN article:

http://msdn.microsoft.com/library/devprods/vs6/vbasic/VBRef98/vbsamppage.htm

Modification Type:MinorLast Reviewed:10/1/2004
Keywords:kbBug kbEvent kbpending kbtemplate kbWebClasses KB279409
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