void ReqQueryInvestorOpenPosition()
{
ThostFtdcQryInvestorPositionDetailField req = new ThostFtdcQryInvestorPositionDetailField();
req.BrokerID = BROKER_ID;
req.InvestorID = INVESTOR_ID;
int iResult = api.ReqQueryInvestorOpenPosition(req, ++iRequestID);
Console.WriteLine("--->>> 请求查询开盘前持仓: " + ((iResult == 0) ? "成功" : "失败"));
}