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Q142445: DOC: CWnd::LockWindowUpdate Does Not Unlock the Window

Article: Q142445
Product(s): Microsoft C Compiler
Version(s): winnt:1.0,2.0,2.1,2.2,4.0; :1.0,1.5,1.51,1.52
Operating System(s): 
Keyword(s): kbdocfix kbdocerr kbMFC KbUIDesign kbVC100bug kbVC150bug kbVC151bug kbVC152bug kbVC200b
Last Modified: 11-MAY-2001

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The information in this article applies to:

- Microsoft Visual C++, versions 1.0, 1.5, 1.51, 1.52, 2.0, 2.1, 2.2, 4.0 
- Microsoft Foundation Classes (MFC) 
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SUMMARY
=======

The documentation for CWnd::LockWindowUpdate() states this function will disable
or reenable drawing for the CWnd object. In the remarks section, the sentence
"Disables or reenables drawing in the given window" is incorrect. Starting with
Visual C++ version 2.0, you should use CWnd::UnlockWindowUpdate() to reenable
drawing to a window locked with CWnd::LockWindowUpdate().

The documentation error was corrected in Visual C++ 4.1.

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

CWnd::LockWindowUpdate() takes no parameters and is implemented as an in-line
call to the Windows function ::LockWindowUpdate(). The function
::LockWindowUpdate() is called with the this->m_hWnd parameter which causes
the window to be locked. To re-enable drawing, NULL should be passed to
::LockWindowUpdate().

In Visual C++ version 2.0 and later, call CWnd::UnlockWindowUpdate() to reenable
drawing to your window. In earlier versions, call the Windows
::LockWindowUpdate( NULL ).

Additional query words: 1.00 1.50 2.00 2.10 2.20 dskbsweep 4.00 4.10

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Keywords          : kbdocfix kbdocerr kbMFC KbUIDesign kbVC100bug kbVC150bug kbVC151bug kbVC152bug kbVC200bug kbVC210bug kbVC220bug kbVC400bug kbVC410fix kbGrpDSMFCATL 
Technology        : kbVCsearch kbVC400 kbAudDeveloper kbMFC kbvc150 kbvc100 kbVC220 kbVC151 kbVC200 kbVC210 kbVC152
Version           : winnt:1.0,2.0,2.1,2.2,4.0; :1.0,1.5,1.51,1.52
Solution Type     : kbfix

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