SAMPLE: CONDOC.EXE Extract Container/Document Info with MFC DAO

The information in this article applies to:

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

SUMMARY

MFC does not currently provide methods for extracting container and document information from DAO collections. The sample, CONDOC.EXE demonstrates how to implement this extraction using MFC DAO objects and, in particular, demonstrates using DAO OLE interfaces not directly available from the MFC DAO classes.

Containers provide an application-independent way for an application to store objects in a database. For example, Microsoft Access uses separate containers to store forms, reports, macros, and modules. This is in a format native only to Access. However, the code below shows how to see which containers are stored in an Access database.

Documents are used to store a specific instance of an application-specific object within a container, such as a form, a report, etc. A container can have more than one document collection. To repeat, Microsoft Access documents and containers are in a format native to Access and not available programatically from other products except through OLE Automation using Access itself.

The following file is available for download from the Microsoft Software Library:

 ~ Condoc.exe (size: 56620 bytes) 

   ARTICLE-ID: Q119591
   TITLE     : How to Obtain Microsoft Support Files from Online Services

MORE INFORMATION

Sample Code

The following code demonstrates how to extract Container and Document information and store it in a Tree View control:

   // Command handler which performs the pertinent operations
   /////////////////////////////////////////////////////////////////////
   //
   void CCONDOCView::OnGetinfoOpenMDB()
   {
       // Prepare the open file dialog
       static char BASED_CODE szFilter[] = _
                             T( "Access Database Files  (*.mdb) | *.mdb" );

       CFileDialog dlg(TRUE, "mdb", NULL,
                       OFN_HIDEREADONLY| OFN_OVERWRITEPROMPT, szFilter);

       // To be retrieved by the open file dialog
       CString strFile;

       // open file dialog
       if(dlg.DoModal() == IDOK)
       {
           strFile = dlg.m_ofn.lpstrFile;

           if(strFile.Right(3).CompareNoCase("mdb") // verify extension
           {
               AfxMessageBox("File Extension error");
               return;
           }
       }

       // you will display the info in a tree control
       CTreeCtrl &tree = GetTreeCtrl();

       // the root of all items!
       HTREEITEM itemDatabase =    tree.InsertItem(
                                  dlg.m_ofn.lpstrFile );

       // An MFC DAO object
       CDaoDatabase db;

       // straight DAO interface pointer variables
       ConDoctainers *pContainers=NULL;
       ConDoctainer* pCon=NULL;
       DAODocuments* pDocuments=NULL;
       DAODocument* pDoc=NULL;

       // To be used for iterating through the collections
       short count;
       short doccount;

       // open the .MDB
       try
       {
           db.Open( strFile );
       }
       catch( CDaoException* e )
       {
           AfxMessageBox( e->m_pErrorInfo->m_strDescription );
           return;
       }

       // Using the DAODatabase interface pointer method contained
       // by the MFC/DAO class CDaoDatabase, you retrieve the interface's
       // set of collections.
       if( FAILED( db.m_pDAODatabase->get_Containers( &pContainers ) ) )
       {
           AfxMessageBox( "Collection not found" );
           db.Close();
           return;
       }

       // Once you have the set of collections, you iterate thru each
       // individual collection, display some of its attributes,
       // then get the document collection on the container,
       // and iterate thru the individual documents, displaying some
       // of the attributes of the documents.
       // See the dbdao.h in the DAOSDK\INCLUDE for more information

       try
       {
           // get the count property of the containers collection
           pContainers->get_Count( &count );

           HTREEITEM itemContainers = tree.InsertItem( _T( "Containers" )
                                                         , itemDatabase );

           // iterate thru the containers
           while( --count > 0 )
           {
               // get an individual container and iterate thru its
               //attributes
               pContainers->get_Item( COleVariant( count, VT_I2 ),
                                                          &pCon );
               BSTR bstr=NULL;

               pCon->get_Name( &bstr );
               CString strName( ( LPCTSTR ) bstr );
               HTREEITEM itemName = tree.InsertItem( strName,
                                                 itemContainers );

               pCon->get_Owner( &bstr );
               CString strOwner(_T("Owner: ") );
               strOwner += (LPCTSTR) bstr;
               HTREEITEM itemOwner = tree.InsertItem( strOwner,
                                                    itemName );

               pCon->get_UserName( &bstr );
               CString strUserName(_T("User Name: ") );
               strUserName += (LPCTSTR) bstr;
               HTREEITEM itemUserName = tree.InsertItem( strUserName,
                                                           itemName );

               // Now get the documents collection
               if( FAILED ( pCon->get_Documents( &pDocuments ) ) )
               {
                   AfxMessageBox( "Collection not found" );
                   db.Close();
                   return;
               }

               // Now get the number of documents contained in the
               // container
               pDocuments->get_Count( &doccount );
               HTREEITEM itemDocuments = tree.InsertItem(
                                           _T( "Documents"), itemName );

               // iterate thru the documents
               while( --doccount > 0 )
               {
                   // get an individual document and iterate thru
                   // some of its attributes.
                   pDocuments->get_Item( COleVariant( doccount, VT_I2 ),
                                                                &pDoc );

                   pDoc->get_Name( &bstr );
                   CString strDocName( ( LPCTSTR ) bstr );
                   HTREEITEM itemDocName = tree.InsertItem( strDocName,
                                                       itemDocuments );

                   pDoc->get_Owner( &bstr );
                   CString strDocOwner(_T("Owner: ") );
                   strDocOwner += (LPCTSTR) bstr;
                   tree.InsertItem( strDocOwner, itemDocName );

                   pCon->get_UserName( &bstr );
                   CString strDocUserName(_T("User Name: ") );
                   strDocUserName += (LPCTSTR) bstr;
                   tree.InsertItem( strDocUserName, itemDocName );
               }
           }
       }
       catch( CDaoException*  e)
       {
           AfxMessageBox( e->m_pErrorInfo->m_strDescription );
           db.Close();
           return;
       }
       db.Close();
   }
   /////////////////////////////////////////////////////////////////////
   // END OF SAMPLE CODE

REFERENCES

Microsoft Jet Database Engine Programmer's Guide, ISBN #: 1-55615-877-7.