userdata.cpp

用户登录模块是用户启动系统与系统交互的第一个窗体

// UersData_Access.cpp: implementation of the UersData_Access class.
//
//////////////////////////////////////////////////////////////////////

#include "stdafx.h"
#include "Login.h"
#include "UserData.h"

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

//导入ADO类型库
#import "c:\Program Files\Common Files\System\ADO\msado15.dll" no_namespace rename("EOF", "ENDOFFILE")

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

CUserData::CUserData()
{

}

CUserData::~CUserData()
{

}

BOOL CUserData::GetPassword(CString *UserName, CString *Password)
{	
	//初始化Com对象
	CoInitialize(NULL);
	try
	{
		//初始化数据库连接对象
		_ConnectionPtr pConn("ADODB.Connection");
		
        //定义数据库连接字符串     
	    _bstr_t Connection ="Provider=Microsoft.Jet.OLEDB.4.0;Data Source=.\\LoginDemo.mdb;Persist Security Info=False";
		//打开数据库连接
		pConn->Open(Connection, "", "", adConnectUnspecified);
		
		//初始化记录集对象
		_RecordsetPtr pRs("ADODB.Recordset");

		CString strSQL;
		strSQL.Format("%s\"%s\"", "Select * From UserInfo Where UserName like ", UserName->GetBuffer(UserName->GetLength()));
		//打开指定记录集
		pRs->Open(_variant_t(strSQL.GetBuffer(strSQL.GetLength())), 
			      _variant_t(pConn, true), 
				  adOpenStatic, 
				  adLockOptimistic, 
				  adCmdText);

		//访问记录集中数据
		if (pRs->BOF)
		{
			//关闭记录集
			pRs->Close();
			pRs.Release();
			//关闭数据库连接
			pConn->Close();
			pConn.Release();
		    UserName->ReleaseBuffer();
			Password->ReleaseBuffer();
			return FALSE;
		}
		else
		{
			strcpy(Password->GetBuffer(255), _bstr_t(pRs->GetCollect("Password")));
			pRs->Close();
			pRs.Release();
			//关闭数据库连接
			pConn->Close();
			pConn.Release();
			UserName->ReleaseBuffer();
			Password->ReleaseBuffer();
			return TRUE;
		}

	}
	catch(_com_error &e)
	{
		::CoUninitialize();
		::AfxMessageBox(e.ErrorMessage());
		return FALSE;
	}
}