operateaccess.cpp

该类可用于操作数据库

// OperateAccess.cpp: implementation of the COperateAccess class.
//
//////////////////////////////////////////////////////////////////////

#include "stdafx.h"
#include "Access.h"
#include "OperateAccess.h"

#ifdef _DEBUG
#undef THIS_FILE
static char THIS_FILE[]=__FILE__;
#define new DEBUG_NEW
#endif

//////////////////////////////////////////////////////////////////////
// Construction/Destruction
//////////////////////////////////////////////////////////////////////

COperateAccess::COperateAccess()
{

}

COperateAccess::~COperateAccess()
{

}

BOOL COperateAccess::ConnectDataBase(CString dbName,CString userID,CString password)
{
	AfxOleInit();

	HRESULT hr;
    try
	{
		hr = m_pConnection.CreateInstance("ADODB.Connection");///创建Connection对象
		if(SUCCEEDED(hr))
		{
			CString connectString;
			connectString.Format("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=%s",dbName);
	//		m_pConnection->ConnectionString="DRIVER={Microsoft   Access   Driver   (file.mdb)}";
			hr = m_pConnection->Open((_bstr_t)connectString,
				(_bstr_t)userID,(_bstr_t)password,adModeUnknown);///连接数据库
			//上面一句中连接字串中的Provider是针对ACCESS2000环境的，对于ACCESS97，
			//需要改为：Provider=Microsoft.Jet.OLEDB.3.51;
		}
	}
	catch(_com_error e)///捕捉异常
	{
		CString errormessage;
		errormessage.Format("连接数据库失败!\r\n错误信息:%s",e.ErrorMessage());
		AfxMessageBox(errormessage); //显示错误信息
		return FALSE;
	} 
//	AfxMessageBox("connect success");
	return TRUE;

}

extern CAccessApp theApp;

_RecordsetPtr COperateAccess::ReadDataBase(CString SQLStatement)
{
	_RecordsetPtr m_pRecordset;
	try
	{
		m_pRecordset.CreateInstance("ADODB.Recordset");
		
		m_pRecordset->Open((_bstr_t)SQLStatement,\
			_variant_t((IDispatch *)theApp.connectAccess.m_pConnection,true),adOpenDynamic,\
			adLockOptimistic,adCmdText);
		
		if(m_pRecordset->adoEOF)
		{
			AfxMessageBox("当前没有记录存在！");
			return NULL;
		}
		return m_pRecordset;
	}
	catch(_com_error e)
	{
		CString errormessage;
		errormessage.Format("操作失败!\r\n错误信息:%s",e.ErrorMessage());
		AfxMessageBox(errormessage); //显示错误信息
		AfxMessageBox(e.Source());   
        AfxMessageBox(e.Description());   
		return NULL;
	}

}

BOOL COperateAccess::OperateRecord(CString SQLStatement)
{
	_variant_t RecordsAffected;
	HRESULT hr;
	try
	{
		hr=theApp.connectAccess.m_pConnection->Execute((_bstr_t)SQLStatement,&RecordsAffected,adCmdText);
		if(SUCCEEDED(hr))
		{
			return TRUE;
		}
		else
			return FALSE;
	}
	catch(_com_error e)
	{
		CString errormessage;
		errormessage.Format("操作失败!\r\n错误信息:%s",e.ErrorMessage());
		AfxMessageBox(errormessage); //显示错误信息
		AfxMessageBox(e.Source());   
        AfxMessageBox(e.Description());   
		return FALSE;
	}
	return TRUE;
}