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Q299799: FIX: Using Class w/ Same Name as a Base Class Causes Error

Article: Q299799
Product(s): Microsoft FoxPro
Version(s): 6.0
Operating System(s): 
Keyword(s): kbOOP kbvfp kbvfp600 kbvfp600bug kbCodeSnippet kbvfp700fix kbvfp700
Last Modified: 29-AUG-2001

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The information in this article applies to:

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

If you create a class by using the DEFINE CLASS command that has the same name
as one of the Visual FoxPro (VFP) base classes, you receive the following error
message when the class is instantiated:

  OLE error code 0x80020006: Unknown name.

CAUSE
=====

Custom classes cannot have the same name as base classes. If you try to compile
the project into a dynamic-link library (DLL), you receive the following error
message:

  Class name is invalid.

STATUS
======

This problem was corrected in Visual FoxPro version 7.0 for Windows.

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

Steps to Reproduce Problem
--------------------------

Save the following code as a program, and then run the program:

  *!* Q299799 FIX: Creating A Class With The Same Name As A Base Class Causes Error
  LOCAL lcVar
  CREATE PROJECT oleclasstest NOWAIT

  lcVar = "DEFINE CLASS Column AS CUSTOM OLEPUBLIC" + CHR(13) + CHR(10) + ;
               "   Test = ''" + CHR(13) + CHR(10) + "ENDDEFINE"

  =STRTOFILE(lcVar, 'Test.prg', .F.)
  _VFP.ACTIVEPROJECT.FILES.ADD('Test.prg')
  _VFP.ACTIVEPROJECT.BUILD('test.dll', 4)
  oObject = CREATEOBJECT('test.Column')
  CLEAR
  ? oObject.Test
  ? oObject.BASECLASS

Additional query words:

======================================================================
Keywords          : kbOOP kbvfp kbvfp600 kbvfp600bug kbCodeSnippet kbvfp700fix kbvfp700 
Technology        : kbVFPsearch kbAudDeveloper kbVFP600
Version           : :6.0
Issue type        : kbbug
Solution Type     : kbfix

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