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

• The Microsoft Foundation Classes (MFC), included with:
  • Microsoft Visual C++, 32-bit Editions, versions 4.0, 4.1, 4.2, 4.2b, 5.0, 6.0

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();
   } 

Keywords : kbcode kbprg kbDAO kbDatabase kbMFC kbVC kbVC400 kbVC410 kbVC420 kbVC500 kbVC600
Version : 4.0 4.1 4.2 4.2b 5.0 6.0
Platform : NT WINDOWS
Issue type : kbhowto