public void ReqUserLogout()
{
ThostFtdcUserLogoutField logoutField = new ThostFtdcUserLogoutField();
logoutField.BrokerID = BROKER_ID;
var ret = mdApi.ReqUserLogout(logoutField, iRequestID++);
HandleStatusInternal("CTP发送用户登出请求：" + (ret == 0 ? "成功" : "失败,返回代码" + ret));
}