/// <summary>
 /// 操作订单(接单,退款等),即改变订单的状态
 /// </summary>
 /// <param name="sellerAccount"></param>
 /// <param name="orderId"></param>
 /// <param name="state"></param>
 /// <returns></returns>
 public bool changeOrderOperator(string sellerAccount, int orderId, string state)
 {
     return(db.orderOperator(sellerAccount, orderId, state));
 }