private void CancelAllOrders() { var ordersToCancel = new List <ThostFtdcOrderField>(); foreach (var order in _trader.UnFinishedOrderFields.Values) { ordersToCancel.Add(order); } foreach (var order in ordersToCancel) { _trader.ReqOrderAction(order.FrontID, order.SessionID, order.OrderRef, order.InstrumentID); } }