VC中ADO

1,StdAfx.h中加入
#import "c:\Program Files\Common Files\System\ado\msado15.dll" no_namespace rename("EOF", "adoEOF")
2,
BOOL C***App::InitInstance()
{
 AfxEnableControlContainer();

 if(!AfxOleInit()) 
 {
  AfxMessageBox("OLE初始化Error");
  return FALSE;
 }

 if (FAILED(pConn.CreateInstance("ADODB.Connection")))
 {
  AfxMessageBox("Create Instance failed!");
  return FALSE;
 }

 CString strSRC = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=.\\Test.mdb;Jet OLEDB:Database Password=80";

 _bstr_t bstrSRC(strSRC);
 if (FAILED(pConn->Open(bstrSRC,"","",-1)))
 {
  AfxMessageBox("Can not open Database!");
  pConn.Release();
  return FALSE;
 }
......
}

void C***Dlg::AccessSql(CString szSql)
{
 _bstr_t bstrSql( szSql );
 pCommand.CreateInstance(__uuidof(Command));
 pCommand->ActiveConnection = pConn;
 pCommand->CommandText = bstrSql;
 pCommand->CommandType = adCmdText;
 pCommand->Parameters->Refresh();
 pRs = pCommand->Execute(NULL,NULL,adCmdUnknown);
}

CString C***Dlg::GetStrValue(CString szSql, CString szFeild)
{
 _bstr_t bstrFeild( szFeild );
 AccessSql( szSql );
 if( pRs->adoEOF )
  return "";
 _variant_t varValue = pRs->GetCollect( bstrFeild );
 CString Value = (char*)_bstr_t(varValue);
 return Value;
}

double C***Dlg::GetDoubleValue(CString szSql, CString szFeild)
{
 _bstr_t bstrFeild( szFeild );
 AccessSql( szSql );
 if( pRs->adoEOF )
  return -1;
 _variant_t varValue = pRs->GetCollect( bstrFeild );
 double Value = (double)varValue;
 return Value;
}

long C***Dlg::GetIntValue(CString szSql, CString szFeild)
{
 _bstr_t bstrFeild( szFeild );
 AccessSql( szSql );
 if( pRs->adoEOF )
  return -1;
 _variant_t varValue = pRs->GetCollect( bstrFeild );
 long Value = (long)varValue;
 return Value;
}