Q186914: HOWTO: Implement Additional Interfaces in an ActiveX Control

Article: Q186914
Product(s): Microsoft Visual Basic for Windows
Version(s): 
Operating System(s): 
Keyword(s): kbGrpDSVB
Last Modified: 11-JAN-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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SUMMARY
=======

This article demonstrates how to implement an additional interface in a Visual
Basic ActiveX control. ActiveX EXE and DLL components are better suited for this
purpose, but it may be desirable, for example, to implement a custom interface
that is present in all of your ActiveX controls. That is the approach taken in
the example shown in this article.

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

Step-by-Step Example
--------------------

1. Start a new ActiveX DLL project in Visual Basic. Change the name of the
  project to BaseClass. Change the name of Class1 to CustomInterface. Insert
  the following code into the CustomInterface class module:

        Public Function testCustomInterface()
        End Function

2. On the File menu, click Add Project to add a new ActiveX Control project.
  Click References on the Project menu, and check the reference to BaseClass.
  Insert the following code into the General Declarations section of the
  UserControl's code module:

        Implements BaseClass.CustomInterface

        Private Function CustomInterface_testCustomInterface() As Variant
           CustomInterface_testCustomInterface = _
                                 "Custom Interface test successful."
        End Function

        Public Function testStandardInterface() As Variant
           testStandardInterface = "Standard Interface test successful."
        End Function

3. Change the name of the project to interfacesControl. Click Add Project on the
  File menu to add a new Standard EXE project. Right-click on Project1 in the
  Project window and select the Set as Start Up option.

4. On the Project menu, click References, and then check the reference to
  BaseClass. Place the UserControl (interfacesControl) on Form1. Add a
  CommandButton to Form1.

5. Insert the following code into the General Declaration section of Form1:

         Private Sub Command1_Click()

            Debug.Print Me.UserControl11.testStandardInterface

            Dim obj As BaseClass.CustomInterface
            Set obj = Me.UserControl11.Object
            Debug.Print obj.testCustomInterface

         End Sub

6. Run the project, click Command1 and note that both interfaces responded in
  the Immediate Window,.

Additional query words: kbDSupport kbDSD kbActiveX kbClientServer kbVBp500 kbVBp600

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Keywords          : kbGrpDSVB 
Technology        : kbVBSearch kbAudDeveloper kbZNotKeyword6 kbZNotKeyword2 kbVB500Search kbVB600Search kbVBA500 kbVBA600 kbVB500 kbVB600
Issue type        : kbhowto

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