ADO使你能够在客户程序中通过数据提供者来方便地处理数据.ADO主要的优点是容易使用、高速、低内存、磁盘占用
在本文的示例工程中我们可以执行存储过程,传递参数给存储过程并接收它的返回值,以下是此过程的主要代码。
{
CString strTmp;
CString m_sdatasource; // Data source name
CString m_sUserID; // User Id
CString m_sPassword; // Password
// GET the above values from the user
//Without creating Datasource we can use database by the following code
/* strTmp.Format( "driver={sql server};"
"server=%s;"
"Database=%s;""UID=%s;""PWD=%s;",
m_server,m_sdatabase,m_sUserID,m_sPassword );*/
strTmp.Format( "dsn=%s;""UID=%s;""PWD=%s;",m_sdatasource,m_sUserID,m_sPassword );
_bstr_t bstrSQLServerConnect;
_bstr_t bstrProc =( L"sp_StartByteImport" );; //Stored procedure name
_variant_t Final;
bstrSQLServerConnect = (LPCTSTR) strTmp;
m_status="Empty File";
_ConnectionPtr Conn1; // connection object pointer
_CommandPtr Cmd1; // command object pointer
_RecordsetPtr Rs1; // recordset object pointer
bool bvalid = false;
try
{
Conn1.CreateInstance( __uuidof( Connection ) ); // Instantiating connection object
Conn1->ConnectionString = bstrSQLServerConnect; // giving the sqlconnection
Conn1->Open( bstrEmpty, bstrEmpty, bstrEmpty ); // open the connection object
Cmd1.CreateInstance( __uuidof( Command ) ); // creating command object
Cmd1->ActiveConnection = Conn1; // giving the connection handle
Cmd1->CommandText = _bstr_t( bstrProc ); // passing the stored procedue
Cmd1->CommandType = adCmdStoredProc; // type
Cmd1->Parameters->Refresh(); // passing string value as argument to stored procedure
Cmd1->Parameters->Item[ _variant_t( (long) 1 ) ]->Value = _variant_t( (LPCTSTR)m_sfilename );
Rs1 = Cmd1->Execute( &vtEmpty, &vtEmpty2, adCmdUnknown ); // executing the stored procedure and storing the recordset value
bvalid = true;
Final = Rs1->Fields->GetItem( _variant_t( 0L ) )->Value; // getting the first column value of the result row
strTmp.Format( "%s", CrackStrVariant( Final) ); // to see the value
// put your code to see all column values
}
catch( CException *e ) // trapping all error messages
{
TCHAR szCause[255];
e->GetErrorMessage(szCause, 255);
m_status=szCause;
}
catch( _com_error &e )
{
m_status=e.ErrorMessage( );
}
catch(...)
{
m_status="Error while executing the Import";
}
//we need to create the stored procedures below before running the application
//CREATE PROCEDURE sp_AddAccountingInfo @nfinal int, @pcDate datetime,
//@pcURL varchar (250), @pcTop varchar (250),
//@pcQueryString varchar (250), @pcBytes int, @pcRequests int AS
/*
Do your operation here
*/
//CREATE PROCEDURE sp_AddAccountingInfo
//@nfinal int,
//@pcDate datetime,
//@pcURL varchar (250),
//@pcTop varchar (250),
//@pcQueryString varchar (250),
//@pcBytes int,
//@pcRequests int
//AS
/*
Put your code here
*/
}