Q135765: PRB: Convert Dialog Doesn’t Appear for OLE Object in MS Excel

Article: Q135765
Product(s): Microsoft C Compiler
Version(s): winnt:
Operating System(s): 
Keyword(s): kbole kbCOMt kbMFC kbVC kbVS97 kbVS600 kbGrpDSMFCATL
Last Modified: 02-AUG-2001

-------------------------------------------------------------------------------
The information in this article applies to:

- The Microsoft Foundation Classes (MFC), used with:
   - Microsoft Visual C++, versions 1.5, 1.51, 1.52 
   - *EDITOR Please do not choose this product*Microsoft Visual C++ 32-bit Edition* use 241, 265, 225, versions 2.0, 2.1, 2.2, 4.0, 4.1 
   - Microsoft Visual C++, 32-bit Enterprise Edition, version 5.0 
   - Microsoft Visual C++, 32-bit Professional Edition, version 5.0 
   - Microsoft Visual C++, 32-bit Enterprise Edition, version 6.0 
   - Microsoft Visual C++, 32-bit Professional Edition, version 6.0 
   - Microsoft Visual C++, 32-bit Learning Edition, version 6.0 
-------------------------------------------------------------------------------

SYMPTOMS
========

When the Edit|<Object>|Convert... menu item is selected for an OLE object
that is embedded within a Microsoft Excel document, the Convert dialog box does
not appear.

CAUSE
=====

Microsoft Excel displays the Convert dialog for an object only if
WriteFmtUserTypeStg has been used to write out a clipboard format and
user-readable name for the contents of the object. The MFC libraries do not call
this function when creating or saving OLE objects.


RESOLUTION
==========

Call WriteFmtUserTypeStg in the Serialize method of your server's document
class.

STATUS
======

This behavior is by design.

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

WriteFmtUserTypeStg should be called as part of your server's implementation of
IPersistStorage::InitNew and IPersistStorage::Save. By default, MFC OLE server
applications do not call WriteFmtUserTypeStg in their implementation of
IPersistStorage::InitNew and IPersistStorage::Save. One simple way to achieve
this functionality in an MFC application is to make the call to
WriteFmtUserTypeStg in the Serialize method of the server's document class.

Steps to Add a Call to WriteFmtUserTypeStg
------------------------------------------

1. Provide a private clipboard format for your object.

  WriteFmtUserTypeStg serializes a clipboard format and user-readable name for
  the contents of an object to its storage. The HIERSVR sample shows how to
  provide a private clipboard format for your object if you do not already have
  one.

2. Add the DoWriteFmtUserTypeStg helper function to your document class.

  This helper function is used to encapsulate retrieving the clipboard format
  and user-readable name when calling WriteFmtUserTypeStg. The code in the
  "Sample Code" section of this article shows how to implement this function
  for the HIERSVR sample.

3. Modify the server document's Serialize() method and add a call to the
  DoWriteFmtUserTypeStg helper function, as shown in the following sample code.

Sample Code
-----------

     void CServerDoc::DoWriteFmtUserTypeStg(LPSTORAGE lpStorage)
     {
        LPOLEOBJECT lpObject = (LPOLEOBJECT)GetInterface(&IID_IOleObject);
        ASSERT(lpObject != NULL);
        CLSID clsid;
        lpObject->GetUserClassID(&clsid);

        LPTSTR pszUserType = NULL;
        OleRegGetUserType(clsid, USERCLASSTYPE_FULL, (LPOLESTR
     *)&pszUserType);

        if (pszUserType)
        {
           WriteClassStg(lpStorage, clsid);
           WriteFmtUserTypeStg(lpStorage, m_cfPrivate,
     (LPOLESTR)pszUserType);
           CoTaskMemFree(pszUserType);
        }
     }

     void CServerDoc::Serialize(CArchive& ar)
     {
       ASSERT(m_pRoot != NULL);

       if(IsEmbedded() && ar.IsStoring())
       {
         ASSERT(m_lpRootStg != NULL);
         DoWriteFmtUserTypeStg(m_lpRootStg);
       }

       SerializeFontInfo(ar);
       m_pRoot->Serialize(ar);
     }

Additional query words: alwaysupdate

======================================================================
Keywords          : kbole kbCOMt kbMFC kbVC kbVS97 kbVS600 kbGrpDSMFCATL 
Technology        : kbAudDeveloper kbMFC
Version           : winnt:
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 1986-2002.