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Q314629: FIX: Object Referenced by Property with ASSIGN Cannot Be Closed

Article: Q314629
Product(s): Microsoft FoxPro
Version(s): 7.0
Operating System(s): 
Keyword(s): kbCOMt kbOOP kbGrpDSFox kbDSupport kbvfp700fix kbvfp700
Last Modified: 24-JAN-2002

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The information in this article applies to:

- Microsoft Visual FoxPro for Windows, version 7.0 
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SYMPTOMS
========

A form or other class is created with a custom property which has an associated
ASSIGN method. When the class is instantiated, and a reference to another object
is assigned to the custom property, you are unable to release the second object,
even if the first object no longer exists.

RESOLUTION
==========

To resolve this problem, obtain the latest service pack for Visual FoxPro for
Windows 7.0. For additional information, please see the following article in the
Microsoft Knowledge Base:

  Q316964 How to Obtain the Latest Visual FoxPro for Windows 7.0 Service Pack

STATUS
======

Microsoft has confirmed this to be a problem in the Microsoft products that are
listed at the beginning of this article. This problem was first corrected in
Visual FoxPro for Windows 7.0 Service Pack 1.

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

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

1. Copy the following code to a new program and run it in Visual FoxPro 7.0:

  LOCAL loMyForm AS FORM, ;
      loCustClass AS CUSTOM

  loCustClass = CREATEOBJECT("MyCustom")
  loMyForm = CREATEOBJECT("FORM")
  loCustClass.ofrm = loMyForm
  loMyForm.SHOW(1)

  DEFINE CLASS MyCustom AS CUSTOM
  	ofrm = .NULL.

  	PROCEDURE ofrm_assign
  		LPARAMETERS vNewVal
  		THIS.ofrm = m.vNewVal
  	ENDPROC
  ENDDEFINE

2. When the form appears, try to close it by using the Close button; you are
  unable to do so. The only way to close the form is to issue a CLEAR ALL
  command from the Command Window.

NOTE: This problem only occurs if there is an ASSIGN method on the property
holding the object reference ("ofrm_assign" in the example code).

Additional query words: close box kbVFP700sp1fix

======================================================================
Keywords          : kbCOMt kbOOP kbGrpDSFox kbDSupport kbvfp700fix kbvfp700 
Technology        : kbVFPsearch kbAudDeveloper kbVFP700
Version           : :7.0
Issue type        : kbbug
Solution Type     : kbfix

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