Q194912: FIX: Add Method of Forms Collection Fails in Executable

Article: Q194912
Product(s): Microsoft Visual Basic for Windows
Version(s): WINDOWS:5.0,6.0
Operating System(s): 
Keyword(s): kbcode kbservicepack kbVBp kbVBp500bug kbVBp600bug kbGrpDSVB kbVS600sp2 kbVS600SP1 kbVS
Last Modified: 24-JUL-2001

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The information in this article applies to:

- Microsoft Visual Basic Learning Edition for Windows, versions 5.0, 6.0 
- Microsoft Visual Basic Professional Edition for Windows, versions 5.0, 6.0 
- Microsoft Visual Basic Enterprise Edition for Windows, versions 5.0, 6.0 
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SYMPTOMS
========

You are using the Add method of the Forms collection to load a form. The code
works correctly in the Visual Basic development environment, but fails with the
following error when the application is made into an executable:

  Run-time error '-2147417848 (80010108)':
  Automation error.

RESOLUTION
==========

You can work around this problem by creating your own Forms collection. A
reference to the form can be added to a collection, and keyed by the Form's
name. This will let you load a form by specifying a text string and referencing
the matching key field in the collection.

There are two options with this approach. You can pre-load the collection with a
reference to all of the forms in the application at startup, which is the
approach used in the following example. You may also load the forms into the
collection as needed. There is slightly more programmatic overhead with the
second approach, because you must check to see if the form is already in the
collection. It is also important to note that adding the forms to the collection
does not load the forms.

Steps to work around this problem are:

1. Start a new Standard EXE project in Visual Basic. Form1 is created by
  default.

2. From the Project menu, add a second form to the project.

3. From the Project menu, add a standard module to the project.

4. Add the following code to the code window of Form1:

        Private Sub Form_Click()
           Dim strFormToLoad As String
           strFormToLoad = "Form2"
           loadForm (strFormToLoad)
        End Sub

        Private Sub Form_Load()
           colForms.Add Form2, "Form2"
        End Sub

5. Add the following code to Module1:

        Public colForms As New Collection

        Public Sub loadForm(strFormName As String)
           Dim frm As Form
           Set frm = colForms(strFormName)
           frm.Show

        End Sub

6. Run the project and click on Form1.

7. Form2 should be loaded.

8. Stop the project.

9. Choose Make Project1.exe from the File menu.

10. Run Project1.exe, and click on Form1.

11. Form2 should load successfully.

STATUS
======

Microsoft has confirmed this to be a bug in the Microsoft products listed at the
beginning of this article.

This bug was corrected in Visual Studio 6.0 Service Pack 3. For more information
about Visual Studio service packs, please see the following articles in the
Microsoft Knowledge Base:

Q194022 INFO: Visual Studio 6.0 Service Packs, What, Where, Why

Q194295 HOWTO: Tell That Visual Studio 6.0 Service Packs Are Installed

MORE INFORMATION
================

Steps to Reproduce Behavior
---------------------------

1. Start a new Standard EXE project in Visual Basic. Form1 is created by
  default.

2. From the Project menu, add a second form to the project.

3. From the Project menu, add a standard module to the project.

4. Add the following code to the code window of Form1:

        Private Sub Form_Click()
           Dim strFormToLoad As String
           strFormToLoad = "Form2"
           loadForm (strFormToLoad)
        End Sub

5. Add the following code to Module1:

        Public Sub loadForm(strFormName As String)
           Dim frm As Form
           Set frm = Forms.Add(strFormName)
           frm.Show

        End Sub

6. Run the project, and click on Form1.

7. Form2 should be loaded.

8. Stop the project.

9. Choose Make Project1.exe from the File menu.

10. Run Project1.exe, and click on Form1.

11. You should receive the error message listed above.

Additional query words:

======================================================================
Keywords          : kbcode kbservicepack kbVBp kbVBp500bug kbVBp600bug kbGrpDSVB kbVS600sp2 kbVS600SP1 kbVS600sp3fix kbCodeSam 
Technology        : kbVBSearch kbAudDeveloper kbZNotKeyword6 kbZNotKeyword2 kbVB500Search kbVB600Search kbVB500 kbVB600
Version           : WINDOWS:5.0,6.0
Issue type        : kbbug
Solution Type     : kbfix

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