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Q191954: PRB: OLE DLL with Exposed Objects Returns Incorrect Description

Article: Q191954
Product(s): Microsoft FoxPro
Version(s): WINDOWS:6.0
Operating System(s): 
Keyword(s): 
Last Modified: 20-AUG-1999

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The information in this article applies to:

- Microsoft Visual FoxPro for Windows, version 6.0 
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SYMPTOMS
========

Under certain circumstances, an OLE .dll with two exposed objects can return the
wrong class description in an error message.

CAUSE
=====

The error routine for a User Interface error in a Visual FoxPro .dll always
takes the class description from the first class.

STATUS
======

Microsoft is researching this problem and will post new information here in the
Microsoft Knowledge Base as it becomes available.

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

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

1. Create a new project called OLETest1.

2. Place the following code into a program file called Test1.prg:

        DEFINE CLASS ErrTest1 AS CUSTOM OLEPUBLIC

           NAME="ErrTest1"
           PROCEDURE gettime
              5 &&Put here to generate an error
              RETURN TIME()
           ENDPROC
        ENDDEFINE

        DEFINE CLASS ErrTest2 AS CUSTOM OLEPUBLIC
           NAME="ErrTest2"
           PROCEDURE gettime
              5 &&Put here to generate an error
              RETURN TIME()
           ENDPROC
        ENDDEFINE

3. Build this into an OLE .dll named OLETest1.

4. Run the following code in the Command window:

        oTmp5=CREATEOBJECT("OLETest1.ErrTest1")
        oTmp6=CREATEOBJECT("OLETest1.ErrTest2")
        *  ?oTmp5.gettime() && Uncomment to show correct error.
        ?oTmp6.gettime()

This produces the following error:

  OLE IDispatch Exception Code 1031 from OLETest1.ErrTest1 ErrTest1:
  ErrTest2.gettime e:\mytest\test1.prg Error Line 13 User Interface operation
  not allowed at this time. 1031

To see the error message referencing the correct class description, uncomment the
third line of the code in step 4 and comment the fourth line.

Additional query words: kbVFp600 kbAutomation kbInterOp

======================================================================
Keywords          :  
Technology        : kbVFPsearch kbAudDeveloper kbVFP600
Version           : WINDOWS:6.0
Issue type        : kbprb
Solution Type     : kbpending

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