void ReqQryInstrumentMarginRate()
{
ThostFtdcQryInstrumentMarginRateField req = new ThostFtdcQryInstrumentMarginRateField();
req.BrokerID = BROKER_ID;
req.InstrumentID = INSTRUMENT_ID;
req.InvestorID = INVESTOR_ID;
req.HedgeFlag = EnumHedgeFlagType.Hedge;
int iResult = api.ReqQryInstrumentMarginRate(req, ++iRequestID);
Console.WriteLine("--->>> 合约保证金率查询请求: " + ((iResult == 0) ? "成功" : "失败"));
}