记录集元素个数

判断记录集中 某一列项为空

_variant_t varValue;
            varValue=pRecordSet->GetCollect (_T("班级"));
            if (varValue.vt!=VT_NULL)
            {
                banjiStr=(LPCTSTR)_bstr_t(varValue);
            }else
                continue;

记录的数目

            _RecordsetPtr pRecordNum;
            numStr.Format (_T("Select * from ClassInfo order by ID"));
            
            pRecordNum->PutCursorLocation(adUseClient);// 添加此语句  才能用 GetRecordCount()得到记录集中的记录个数
            pRecordNum->Open(
            (LPCTSTR)numStr,
            m_pConnectionStu.GetInterfacePtr(),
            adOpenStatic,
            adLockOptimistic,
            adCmdText
            );
            
            if(pRecordNum->adoBOF)
                return;
            else
                pRecordNum->MoveFirst();
            
            int num=pRecordNum->GetRecordCount();
            pRecordNum->MoveLast();