HOWTO: Passing a License Key to Classes Generated by #import

ID: Q170461

The information in this article applies to:

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

SUMMARY

This article only applies to ADO version 1.0. With ADO 1.5 and above you do not need a licence key. ADO 1.5 and above are redistributed with MDAC(Microsoft Data Access Components) package. So to get the latest version of ADO, download latest version of MDAC from http://www.microsoft.com/data.

The Following Information Applies to ADO 1.0

The #import directive is used to incorporate information from a type library, but makes no provision for a license key. If you installed the OLE DB SDK or Internet Information Server 3.0, then the license key is automatically created in the registry.

However, if your application is redistributed to machines that have not had either OLE DB SDK or Internet Information Server 3.0 installed on them, you need to programmatically provide the ADO License Key. This is necessary regardless of the development environment you are using to manipulate ADO.

This article is one of a series dealing with redistribution of Microsoft Data Access Components (MDAC), including ODBC, OLE DB, ADO, RDS, the MDAC Standalone, MDAC Redistribution, and the Data Access SDK. The white paper "Redistributing Microsoft Data Access Components" presents a comprehensive overview of this subject, including referencing the content in this Knowledge Base article. You can find this white paper at the following location:

http://www.microsoft.com/msdn/news/feature/datajul98/redistmdac.htm

MORE INFORMATION

The following is a typical #import statement:


#import "msado10.dll" no_namespace rename( "EOF", "adoEOF" )

When using #import to generate classes for ADO, your code to manipulate a recordset might look like this:


   HRESULT        hr;
   _ConnectionPtr pConn;
   _bstr_t        bstrConnect = SysAllocString( L"driver={sql server};"
                                                L"Database=pubs;"
                                                L"UID=sa;PWD=;" );

   hr = pConn.CreateInstance(__uuidof(Connection));
   if (!FAILED(hr))

      pConn->ConnectionString = bstrConnect;

This will work on any machine that has had the ADO 1.0 License Key already installed. However, if the license key is not installed, this code will not work. The code sample below is functionally equivalent but demonstrates how to create an ADO object using a license key.

Sample Code


   BSTR            LicKey;
   IClassFactory2  *pIUnknown = NULL;
   IUnknown        *pOuter    = NULL;
   HRESULT         hr;
   _ConnectionPtr  pConn;
   _bstr_t         bstrConnect = SysAllocString( L"driver={sql server};"
                                                 L"Database=pubs;"
                                                 L"UID=sa;PWD=;" );

   LicKey = SysAllocString( L"gxwaezucfyqpwjgqbcmtsncuhwsnyhiohwxz" );

   // 
   hr = CoGetClassObject( __uuidof(Connection),
                          CLSCTX_INPROC_SERVER,
                          NULL,
                          IID_IClassFactory2,
                          reinterpret_cast<void**>(&pIUnknown) );
   if( !FAILED( hr ) )
   {

      pIUnknown->CreateInstanceLic( pOuter,
                                    NULL,
                                    __uuidof(_Connection),
                                    LicKey,
                                    reinterpret_cast>void**> (&pConn) );
   }

   if( !FAILED( hr ) )
      pConn->ConnectionString = bstrConnect;

   SysFreeString( LicKey );

REFERENCES

Additional query words: adoengdb

Keywords : kbADO100 kbCompiler kbDatabase kbMFC kbVC500 kbGrpVCDB kbGrpMDAC kbDSupport
Version : winnt:5.0
Platform : winnt
Issue type : kbhowto