BUG: Blank Window Appears Instead of Help File Contents

• Microsoft Visual Basic Learning, Professional, and Enterprise Editions for Windows, version 5.0

SYMPTOMS

When you set the HelpCommand property of a Common Dialog control to cdlHelpContents and then use the ShowHelp method to display the contents of a Help file, Windows Help appears with a blank window. The contents of the Help file is not displayed. The same behavior is exhibited if you set the HelpCommand property to cdlHelpIndex to display the index of a Help file.

RESOLUTION

Workaround #1

To display the contents or index of your Help file with the ShowHelp method, first set the HelpCommand property of the Common Dialog control to the value &HB. This value corresponds to the HELP_FINDER constant 0x000b in WINUSER.H. When you use this constant, the Help window appears with the last active tab. For example, if the Index tab was selected when this window was last shown, then it will be the active tab when help is shown again:

      CommonDialog1.HelpFile = _
         "C:\Program Files\DevStudio\VB\Samples\Samples.hlp"
      CommonDialog1.HelpCommand = &HB
      CommonDialog1.ShowHelp

Workaround #2

To display the Index tab of your Help file, regardless of which tab was active when the Help file was last shown, set the HelpCommand property of the Common Dialog control to cdlHelpPartialKey:

      CommonDialog1.HelpFile = _
         "C:\Program Files\DevStudio\VB\Samples\Samples.hlp"
      CommonDialog1.HelpCommand = cdlHelpPartialKey
      CommonDialog1.ShowHelp

STATUS

Microsoft has confirmed this to be a bug in the Microsoft products listed at the beginning of this article. We are researching this bug and will post new information here in the Microsoft Knowledge Base as it becomes available.

MORE INFORMATION

Steps to Reproduce Behavior

1. Start a new project in Visual Basic.

2. Click Components on the Project menu. Check "Microsoft Common Dialog 5.0" and click OK.

3. Add a Common Dialog control to Form1.

4. Add the following code to the Form_Click event of Form1:

         CommonDialog1.HelpFile = _
            "C:\Program Files\DevStudio\VB\Samples\Samples.hlp"
         CommonDialog1.HelpCommand = cdlHelpContents
         CommonDialog1.ShowHelp
   
   

5. Press the F5 key to run the application.

6. Click the form and note that Windows Help appears but the Help file contents are not displayed.