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Q158822: PRB: ADDOBJECT Gives "A member object…already exists" Error

Article: Q158822
Product(s): Microsoft FoxPro
Version(s): WINDOWS:5.0
Operating System(s): 
Keyword(s): 
Last Modified: 11-DEC-1999

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The information in this article applies to:

- Microsoft Visual FoxPro for Windows, version 5.0 
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SYMPTOMS
========

Adding an object to a container after removing that object, may result in the
following error message:

  A member object with this name already exists

STATUS
======

This behavior is by design.

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

Visual FoxPro does not allow the removal of an object if code for that object is
currently executing. Attempts to remove the object are delayed until the object
code has completed execution, and Visual FoxPro does not display any warning or
errors. This leads users to believe that the object has been removed when it has
not been removed. Trying to add the object back into the container causes the "A
member object with this name already exists" error because the object was not
removed and is still a part of the container.

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

1. Execute the following code (which instantiates a Form with a CommandButton
  object):

        PUBLIC oF
        oF = CreateObject('form')
        oF.AddObject('oCont','Cont')
        oF.Show()

        DEFINE CLASS Cont AS Container
          ADD OBJECT oCmd AS Cmd
          Visible = .t.
        ENDDEFINE

        DEFINE CLASS Cmd AS CommandButton
          Top = 50
          Visible=.t.
          PROCEDURE click
            oF.RemoveObject('ocont')     && No error occurs
            oF.AddObject('ocont','cont') && Produces error
          ENDPROC
        ENDDEFINE

2. When the Form appears, click on the command button. The "A member object with
  this name already exists" error message appears.

Additional query words: VFoxWin kbdse

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Keywords          :  
Technology        : kbVFPsearch kbAudDeveloper kbVFP500
Version           : WINDOWS:5.0

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