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Q189911: PRB: REDIMENSION an Array Passed by Reference in DLL Fails

Article: Q189911
Product(s): Microsoft FoxPro
Version(s): WINDOWS:6.0
Operating System(s): 
Keyword(s): 
Last Modified: 17-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
========

Attempting to REDIMENSION an array that has been passed by reference from within
a Visual FoxPro COM object will result in the following error message:

  OLE IDispatch exception code 302 from Visual FoxPro for Windows: Data type
  mismatch...

CAUSE
=====

An array that has been passed by reference to a Visual FoxPro COM object cannot
be redimensioned from within the COM object.

RESOLUTION
==========

The array must be redimensioned in the client before passing the reference to
the Visual FoxPro COM object.

STATUS
======

This behavior is by design.

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

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

1. Create a new project named MyDLL.

2. Add a new program to the project containing the following code:

        DEFINE Class VFPArray As Custom OlePublic
           PROCEDURE GetArray(aRetVal)
              LOCAL x
              FOR x = 1 To 50
                 DIMENSION aRetVal[x]
                 aRetVal[x] = x
              NEXT x
           ENDPROC
        ENDDEFINE

3. Build the project into a COM DLL.

4. Run the following code from Visual FoxPro:

        ox = CreateObject("MyDLL.VFPArray")
        DIMENSION myarray[1]
        ComArray(ox,11)
        ox.GetArray(@myarray)

NOTE: The above mentioned error message will occur when calling the GetArray
method in the COM object.

Additional query words:

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

=============================================================================

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