DOCUMENT:Q189382 17-JUL-2001 [visualc] TITLE :PRB: CWnd::m_nMsgDragList Not Exported by the MFC DLL PRODUCT :Microsoft C Compiler PROD/VER:winnt:5.0 OPER/SYS: KEYWORDS:kbnokeyword kbDLL kbMFC kbVC500 kbGrpDSMFCATL kbArchitecture ====================================================================== ------------------------------------------------------------------------------- The information in this article applies to: - The Microsoft Foundation Classes (MFC), used with: - Microsoft Visual C++, 32-bit Enterprise Edition, version 5.0 - Microsoft Visual C++, 32-bit Professional Edition, version 5.0 ------------------------------------------------------------------------------- SYMPTOMS ======== When you use the protected CWnd member m_nMsgDragList in an application or DLL that is linked to the MFC shared DLL, a LNK2001 unresolved external error occurs. This error does not occur when you link to the static MFC library. CAUSE ===== CWnd::m_nMsgDragList is not exported from the MFC DLL. RESOLUTION ========== To workaround this problem, call RegisterWindowMessage with the DRAGLISTMSGSTRING message and use the value returned instead of CWnd::m_nMsgDragList. For example: UINT nMsgDragList = ::RegisterWindowMessage(DRAGLISTMSGSTRING); STATUS ====== This behavior is by design. MORE INFORMATION ================ CWnd::m_nMsgDragList is an undocumented member of the CWnd class and is subject to change. The most common use of CWnd::m_nMsgDragList occurs when you override OnChildNotify in a CWnd derived class. (c) Microsoft Corporation 1998, All Rights Reserved. Contributions by Isaac L. Varon, Microsoft Corporation Additional query words: ====================================================================== Keywords : kbnokeyword kbDLL kbMFC kbVC500 kbGrpDSMFCATL kbArchitecture Technology : kbAudDeveloper kbMFC Version : winnt:5.0 Issue type : kbprb ============================================================================= THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. MICROSOFT DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL, CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. SOME STATES DO NOT ALLOW THE EXCLUSION OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES SO THE FOREGOING LIMITATION MAY NOT APPLY. Copyright Microsoft Corporation 2001.