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Q131100: INFO: DoDragDrop() Parameter Documented Incorrectly

Article: Q131100
Product(s): Microsoft C Compiler
Version(s): winnt:2.0,2.1,5.0
Operating System(s): 
Keyword(s): kbole kbdocfix kbdocerr kbActiveX kbMFC kbVC500bug kbVC600fix kbGrpDSMFCATL
Last Modified: 06-MAY-2001

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The information in this article applies to:

- The Microsoft Foundation Classes (MFC), used with:
   - Microsoft Visual C++ for Windows, 16-bit edition, versions 1.5, 1.51, 1.52 
   - Microsoft Visual C++, 32-bit Editions, versions 2.0, 2.1 
   - Microsoft Visual C++, 32-bit Enterprise Edition, version 5.0 
   - Microsoft Visual C++, 32-bit Professional Edition, version 5.0 
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SUMMARY
=======

The documentation for COleClientItem::DoDragDrop(),
COleServerItem::DoDragDrop(), and COleDataSource::DoDragDrop() give the
following incorrect information for the lpRectStartDrag parameter:

In Visual C++ Prior to 5.0
--------------------------

  lpRectStartDrag:

  Pointer to the rectangle that defines where the drag
  actually starts. It does not start until the mouse cursor leaves the
  rectangle. If NULL, a default rectangle is used so that the drag
  starts when the mouse cursor moves one pixel.

In Visual C++ 5.0
-----------------

Call the DoDragDrop member function to perform a drag-and-drop operation. The
drag-and-drop operation does not start immediately. It waits until the mouse
cursor leaves the rectangle specified by lpRectStartDrag or until a specified
number of milliseconds have passed. If lpRectStartDrag is NULL, the size of the
rectangle is one pixel. The delay time is specified by the DragDelay value in
the [Windows] section of WIN.INI. If this value is not in WIN.INI, the default
value of 200 milliseconds is used.

Correction
----------

The documentation for the lpRectStartDrag parameter for DoDragDrop() should be:

  lpRectStartDrag:

  Pointer to the rectangle that defines where the drag
  actually starts. It does not start until the mouse cursor leaves the
  rectangle or until a specific number of milliseconds has passed. If
  NULL, a default rectangle is used so that the drag starts when the
  mouse cursor moves one pixel. The number of milliseconds is specified
  by a registry key setting. The value can be found in the Windows NT
  system registry under the key HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\ 
  Windows\NT\CurrentVersion\IniFileMapping\win.ini\Windows\DragDelay,
  or in the WIN.INI file under the [Windows] section if running under
  Windows version 3.x. If the key is not present, a default value of 200
  milliseconds is used.

This problem was corrected in Visual C++ version 6.0 for Windows.

Additional query words:

======================================================================
Keywords          : kbole kbdocfix kbdocerr kbActiveX kbMFC kbVC500bug kbVC600fix kbGrpDSMFCATL 
Technology        : kbAudDeveloper kbMFC
Version           : winnt:2.0,2.1,5.0
Solution Type     : kbfix

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