FILE: Adovcbtd.exe #import Using UpdateBatch and CancelBatch

ID: Q181733

The information in this article applies to:

ActiveX Data Objects (ADO), version 1.5 included with:

    - Microsoft Visual C++, 32-bit Editions, version 5.0

SUMMARY

The Adovcbtd.exe sample demonstrates CancelBatch, UpdateBatch, AddNew, Delete, Move, and other ActiveX Data Objects (ADO) Recordset methods using smart pointers and #import. Using #import is the preferred way for Visual C++ programmers to use ADO.

The program is written and designed to demonstrate how to get started with ADO via #import.

MORE INFORMATION

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

 ~ Adovcbtd.exe (size: 90008 bytes)

For more information about downloading files from the Microsoft Software Library, please see the following article in the Microsoft Knowledge Base:

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

The sample undefines EOF in Stdafx.h to prevent a conflict. The following three lines are from the Stdafx.h file:

   #undef EOF
   #import <Msado15.dll> rename_namespace("ado15")
   //  Please see the #import Directive help in InfoViewer
   rename_namespace("ado15")

Msado15.dll has to be located on the same drive as the Windows System directory, and in a path \program files\common files\system\ado. You can configure Visual C++ to use this path to search for the ADO .dll, eliminating the need to specify the explicit path within your #import statement, just as you would configure the location of header files used by

#include. The sample renames the namespace to prevent collisions with other

COM libraries.

The sample shows what ADO capabilities are supported by the driver and also uses a Microsoft Access database. However, you can replace it with other data sources in the code.

With certain combinations of Delete/Add New/Next/Prev, it is possible to get an OLE error. The code is provided as a sample only and is not for production purposes.

Note that you cannot pass a connection object in the recordset Open method in ADO version 1.5. You must use the PutRefActiveConnection method. This differs from ADO 1.0 and Visual Basic (VB). The following code shows how to open a recordset using an ODBC Data Source Name (DSN). The sample file opens the recordset using an alternate (DSN-less) method. Note that error checking has been omitted for clarity in the code given below, but is included in the sample file.

Here is the code:

   void CAdxDlg::OnBUTopen()
   {
      _ConnectionPtr  Conn1;
      HRESULT hr=Conn1.CreateInstance( __uuidof( Connection ) );
      _bstr_t bsDSN   = (L"Student Registration");
      _bstr_t bsEmpty = L"";
      Conn1->ConnectionString = bsDSN;
      Conn1->Open( bsEmpty, bsEmpty, bsEmpty, -1 );
      hr=Rs1.CreateInstance( __uuidof( Recordset ) );
      Rs1->PutRefActiveConnection( Conn1 );
      _bstr_t bsSel(L"SELECT * FROM Student");
      Rs1->Open(bsSel,vtMissing,adOpenKeyset,adLockBatchOptimistic,-1);
   }

For additional information about running the sample file, please refer to the Readme.txt file included with the sample.

REFERENCES

For additional information on using ADO with #import, please see the following articles in the Microsoft Knowledge Base:

   ARTICLE-ID: Q182389
   TITLE     : FILE: Adovcbm.exe ADO 1.5 with #import and Getrows/Bookmarks

   ARTICLE-ID: Q169498
   TITLE     : INFO: Extracting Error Information from ADO in C++ with
               #import

   ARTICLE-ID: Q174565
   TITLE     : FILE: Adovc.exe Demonstrates How to Use ADO with Visual C++

   ARTICLE-ID: Q177939
   TITLE     : INFO: Changes in ADO 1.5 That Affect Visual C++/J++
               Programmers

Additional query words: CancelUpdate _com_error MoveNext MoveLast CancelBatch adAffectAll Supports Delete

Keywords          : kbfile kbADO kbVC 
Version           : WINDOWS:1.5
Platform          : WINDOWS
Issue type        : kbhowto

Last Reviewed: October 30, 1998