error:Invalid variant type conversion,adoquery的问题
我用ado query算总和,可是总是出现类型转换错误,
Variant pMonthEarn;
Variant pYourTime;
pYourTime="2001-7-1";
DMod1->AQMonthEarn->Close(); //AQMonthEarn--我的adoquery的名字
DMod1->AQMonthEarn->Prepared=true;
DMod1->AQMonthEarn->Parameters->ParamValues["YourTime"]= pYourTime;
pMonthEarn=DMod1->AQMonthEarn->Parameters->ParamValues["MonthEarn"];
DMod1->AQMonthEarn->Open();
DMod1->AQMonthEarn->ExecSQL();
DMod1->AQMonthEarn->Refresh();
在parameter的属性设置中,参数YourTime设为ptInput,ftDateTime;MonthEarn设为ptOutPut,ftFloat.