Q172312: PRB: WithEvents Does Not Work with Remote Automation

Article: Q172312
Product(s): Microsoft Visual Basic for Windows
Version(s): WINDOWS:5.0
Operating System(s): 
Keyword(s): kbGrpDSVBDB
Last Modified: 11-JAN-2001

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The information in this article applies to:

- Microsoft Visual Basic Control Creation Edition for Windows, version 5.0 
- Microsoft Visual Basic Learning Edition for Windows, version 5.0 
- Microsoft Visual Basic Professional Edition for Windows, version 5.0 
- Microsoft Visual Basic Enterprise Edition for Windows, version 5.0 
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SYMPTOMS
========

When attempting to raise a remote event across Remote Automation, the following
run-time error appears:

  -2147467259(80004005) , Automation error

CAUSE
=====

Remote Automation does not currently support the use of WithEvents.

RESOLUTION
==========

To support remote events with Visual Basic 5.0, use DCOM instead of Remote
Automation. You can also use callbacks to simulate raising events remotely.

STATUS
======

This behavior is by design.

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

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

Use the following steps on the server machine:

1. Start Visual Basic 5.0 and create a new ActiveX EXE project.

2. From the Project menu, selectProject properties and change the Project name
  to "Projtest."

3. Add a Class Module and change its name to "Testclass."

4. In Testclass' Code window, input following code:

        Public Event propchange(newv As String)
        Private propt As String

        Public Sub showfrm()
              MsgBox "asdfl"

        End Sub

        Public Property Get testp() As String
              testp = propt
        End Property

        Public Property Let testp(ByVal vNewValue As String)
              propt = vNewValue
              RaiseEvent propchange(propt)
        End Property

5. On the File menu, click "Make ProjTest.exe."

6. Copy the corresponding .exe, .tlb, and .vbr files to the client machine.

7. Start the Automation Manager and the RemAuto Connection Manager to set
  necessary server-side configuration for using Projtest.testclass for Remote
  Automation.

Use the following steps on the client machine:

1. Run Projtest.exe, which was copied from the Server side in the above steps.

2. Start the RemAuto Connection Manager to set necessary Client-side
  configuration for using Projtest.testclass.

3. Launch Visual Basic 5.0 and create a new Standard EXE project with a standard
  form.

4. From the Project menu, click References and select the "Projtest" box.

5. In Form1's Code window, input following code:

        Public WithEvents eventp As testclass

        Private Sub eventp_propchange(newv As String)
             MsgBox newv
        End Sub

        Private Sub Form_Load()
             Dim a As New testclass
             a.showfrm
             Set eventp = a
             a.testp = "test string"
         End Sub

6. Run the project and check if the Remote Automation connection is correct, the
  message box should pop up on the server-side machine.

7. Click OK to close the message box on the server-side machine.

Result
------

When the line "Set eventp = a" executes, you will get the following run- time
error:

  -2147467259(80004005) , Automation error

Expected behavior
-----------------

A message box should appear on the client-side machine because the server raised
the Propchange event.

NOTE: If both the client and the server are running on the same machine (with
local automation), you will see the expected behavior.

======================================================================
Keywords          : kbGrpDSVBDB 
Technology        : kbVBSearch kbAudDeveloper kbZNotKeyword6 kbZNotKeyword2 kbVB500Search kbVBA500Search kbVBA500 kbVB500 kbZNotKeyword3
Version           : WINDOWS:5.0
Issue type        : kbprb

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