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Q299322: FIX: Error with Repeated AddObject/RemoveObject Calls

Article: Q299322
Product(s): Microsoft FoxPro
Version(s): 5.0,5.0a,6.0
Operating System(s): 
Keyword(s): kbOOP kbvfp kbvfp500bug kbvfp600bug kbGrpDSFox kbDSupport kbvfp700fix kbvfp700kbfixlist
Last Modified: 29-AUG-2001

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The information in this article applies to:

- Microsoft Visual FoxPro for Windows, versions 5.0, 5.0a, 6.0 
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SYMPTOMS
========

When a program makes repeated calls to the AddObject and RemoveObject methods,
the following error message may be received:

  Too Many Names Used

CAUSE
=====

Visual FoxPro is not releasing unused names from the internal names table used
to keep track of created objects.

STATUS
======

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

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

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

1. Paste the following code in a new program:

  ON KEY LABEL F5 DO CleanUp
  CLEAR ALL
  CLEAR

  LOCAL lcVarName,  lni, loCont
  PUBLIC glKeepGoing
  loCont = CREATEOBJECT("Container")
  glKeepGoing = .T.
  lni = 0

  DO WHILE glKeepGoing
  	lni = lni+1
  	lcVarName = "ln" + SYS(2015)
  	loCont.ADDOBJECT(lcVarName ,"Line")
  	loCont.REMOVEOBJECT(lcVarName)
  	IF MOD(lni,500) = 0
  		? lni, SYS(1011), SYS(1016)
  		_CALCMEM = lni && The Calculator Memory will persist 
                                 && through the following CLEAR ALL.
  		CLEAR ALL
  		LOCAL loCont, lni, lcVarName
  		glKeepGoing = .T.
  		loCont = CREATEOBJECT("Container")
  		lni = INT(_CALCMEM)
  	ENDIF
  ENDDO

  PROCEDURE CleanUp
  	glKeepGoing = .F.
  	ON KEY LABEL F5
  ENDPROC

2. Save and then run the code (the program name is not important).

  You can press F5 at any time to end the running program. The numbers printed
  to the screen are loop iterations. They show the value of SYS(1011) (Number
  of Memory Handles) and the value of SYS(1016) (User Object Memory Use). The
  error occurs when the number of iterations reaches around 64000.

(c) Microsoft Corporation 2001, All Rights Reserved. Contributions by Trevor
Hancock, Microsoft Corporation.


Additional query words:

======================================================================
Keywords          : kbOOP kbvfp kbvfp500bug kbvfp600bug kbGrpDSFox kbDSupport kbvfp700fix kbvfp700 kbfixlist
Technology        : kbVFPsearch kbAudDeveloper kbVFP500 kbVFP600 kbVFP500a
Version           : :5.0,5.0a,6.0
Issue type        : kbbug
Solution Type     : kbfix

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

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