Q152688: HOWTO: Change the Name of a Microsoft Access Field w/MFC DAO

Article: Q152688
Product(s): Microsoft C Compiler
Version(s): 4.0 4.1 4.2 4.2b 5.0 6.0
Operating System(s): 
Keyword(s): kbcode kbProgramming kbDAOsearch kbDatabase kbMFC kbVC kbVC400 kbVC410 kbVC420 kbVC500
Last Modified: 04-AUG-2001

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The information in this article applies to:

- The Microsoft Foundation Classes (MFC), included with:
   - Microsoft Visual C++, 32-bit Editions, versions 4.0, 4.1 
   - Microsoft Visual C++, 32-bit Enterprise Edition, version 4.2 
   - Microsoft Visual C++, 32-bit Professional Edition, version 4.2 
   - Microsoft Visual C++, 32-bit Enterprise Edition, version 4.2b 
   - Microsoft Visual C++, 32-bit Professional Edition, version 4.2b 
   - 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 
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SUMMARY
=======

The MFC DAO classes do not provide a programmatic way to change the name of a
Microsoft Access field. The example code in this article changes a field's Name
property by directly calling DAO using the m_pDAOFields data member of
CDaoTableDef.

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

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

     /////////////////////////////////////////////////////////////////// 
     // CTabDef - class definition

     class CTabDef : public CDaoTableDef
     {
     public:
         CTabDef( CDaoDatabase* pDB) : CDaoTableDef( pDB )
         { }

         ~CTabDef() {}

         void ChangeFieldProperty(LPCTSTR szOldName, LPCTSTR szNewName);
     };

     ///////////////////////////////////////////////////////////////// 
     // CTabDef - implementation
     void CTabDef::ChangeFieldProperty( LPCTSTR szOld, LPCTSTR szNew )
     {
       // To be used as an "in" param to get_Item
       DAOField* pDAOField = NULL;

       if (m_pDAOFields == NULL)
            InitFieldsCollection();

         // Enumerate the fields collection and find the field.
         // Then replace the name property with the new string.
         try
         {
         DAO_CHECK( m_pDAOFields->get_Item(
                    COleVariant(szOld, VT_BSTRT), &pDAOField ) );

           DAO_CHECK( pDAOField->put_Name(
                    COleVariant(szNew, VT_BSTRT).bstrVal ) );
         }
         catch( CDaoException* e )
         {
             AfxMessageBox( e->m_pErrorInfo->m_strDescription );
             goto term;
         }
         catch(...)
         {
             AfxMessageBox( _T( "unknown exception" ) );
             goto term;
         }

         term:
         if( pDAOField )
             pDAOField->Release();
     }

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Keywords          : kbcode kbProgramming kbDAOsearch kbDatabase kbMFC kbVC kbVC400 kbVC410 kbVC420 kbVC500 kbVC600 
Technology        : kbAudDeveloper kbMFC
Version           : 4.0 4.1 4.2 4.2b 5.0 6.0
Issue type        : kbhowto

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