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开发平台：
Visual C++

ADOConnection.cpp：源码内容
							#include "ADOConnection.h"
//Initialize or UnInitialize the ADO connection.
bool	CADOConnection::ADO_Initialize()
{
	return !FAILED(::CoInitialize(NULL));
}
void	CADOConnection::ADO_UnInitialize()
{
	::CoUninitialize();
}
// Construction/Destruction
CADOConnection::CADOConnection()
{
	if( !CADOConnection::ADO_Initialize() ){
		throw	new CADOException( "CADOConnection::CADOConnection", "ADO_Initialize() Failed." );
	}
	
	this->m_bConnected = false;
	this->m_pConnection = NULL;
	this->m_sConnectionString.erase();
	//Create the connection object
	try{
		HRESULT hr = m_pConnection.CreateInstance("ADODB.Connection");
		if(FAILED(hr)){
			throw	new CADOException( "CADOConnection::CADOConnection", "Create ADO Connection Instance Failed." );
		}
	}
	catch(_com_error e){
		throw	new CADOException( "CADOConnection::CADOConnection", e.Description() );
	}
}
CADOConnection::~CADOConnection()
{
	this->Destroy();
}
//get the connection smart ptr.
_ConnectionPtr	CADOConnection::getConnectionPtr()
{
	return this->m_pConnection;
}
//Set the connection string and connecting mode.
bool	CADOConnection::Create(LPCSTR lpszConnect,			
			   ConnectModeEnum	cmMode,
			   CursorLocationEnum clCursorLocation,
			   int	nConnectionTimeOut)
{
	if( !_STREMPTY(lpszConnect) )
	{		
		//store the connection string.
		this->m_sConnectionString = lpszConnect;
		try{
			//set the connection properties.
			m_pConnection->CursorLocation =	clCursorLocation;
			
			this->m_bConnected = _COMOK(
				m_pConnection->Open(_bstr_t(lpszConnect), "", "", cmMode)
			);
			return this->m_bConnected;
		}
		catch(_com_error e){
			throw	new CADOException( "CADOConnection::Create", e.Description() );
		}
	}
	return false;
}
//destroy the connection.
void	CADOConnection::Destroy()
{
	try{
		//close the db connection
		if(this->IsActived()){
			this->m_pConnection->Close();
			this->m_pConnection = NULL;
			this->m_sConnectionString.erase();
			this->m_bConnected  = false;
		}
	}
	catch(_com_error e){
		throw	new CADOException( "CADOConnection::Destroy", e.Description() );
	}
}
//get the connection whether is opened.
bool	CADOConnection::IsActived()
{
	return this->m_bConnected;
}
//get the connection string.
LPCSTR	CADOConnection::GetConnectionString(void)
{
	return this->m_sConnectionString.data();
}
//Transaction processing.
bool	CADOConnection::BeginTransaction()
{
	try{
		return SUCCEEDED( m_pConnection->BeginTrans() );
	}
	catch(_com_error e){
		throw	new CADOException( "CADOConnection::BeginTransaction", e.Description() );
	}
	return false;
}
bool	CADOConnection::CommitTransaction()
{
	try{
		return SUCCEEDED( m_pConnection->CommitTrans() );
	}
	catch(_com_error e){
		throw	new CADOException( "CADOConnection::CommitTransaction", e.Description() );
	}
	return false;
}
bool	CADOConnection::RollBackTransaction()
{
	try{
		return SUCCEEDED( m_pConnection->RollbackTrans() );
	}
	catch(_com_error e){
		throw	new CADOException( "CADOConnection::RollBackTransaction", e.Description() );
	}
	return false;
}
//Execute some sql statements.
_RecordsetPtr	CADOConnection::Execute(LPCSTR lpszSQLText, CommandTypeEnum ctCmdType)
{
	_variant_t vRecAffected;
	
	vRecAffected.Clear();
	
	//m_pConnection->CommandTimeout	=	0;
	return	this->m_pConnection->Execute(
			_bstr_t(lpszSQLText), &vRecAffected, ctCmdType);	
}
//open schema.
_RecordsetPtr	CADOConnection::OpenSchema(SchemaEnum Schema)
{
	_RecordsetPtr rs = NULL;
	// Get a list of tables and dump list to console.
	rs = m_pConnection->OpenSchema( Schema );
	return rs;
}

						