/// <summary>
        /// 关闭订单接口
        /// </summary>
        /// <returns></returns>
        public JsonResult CloseOrder(WXM_TRADE_Model trade)
        {
            string nonceStr = Senparc.Weixin.MP.TenPayLibV3.TenPayV3Util.GetNoncestr();

            Senparc.Weixin.MP.TenPayLibV3.RequestHandler packageReqHandler = new Senparc.Weixin.MP.TenPayLibV3.RequestHandler(null);

            //设置package订单参数
            packageReqHandler.SetParameter("appid", AppId);          //公众账号ID
            packageReqHandler.SetParameter("mch_id", MchId);          //商户号
            packageReqHandler.SetParameter("out_trade_no", trade.TRADE_NO);                 //填入商家订单号
            packageReqHandler.SetParameter("nonce_str", nonceStr);              //随机字符串

            string sign = packageReqHandler.CreateMd5Sign("key", Key);

            packageReqHandler.SetParameter("sign", sign);                        //签名

            string data = packageReqHandler.ParseXML();

            var result = Senparc.Weixin.MP.AdvancedAPIs.TenPayV3.CloseOrder(data);
            var res =System.Xml.Linq.XDocument.Parse(result);
            string return_code = res.Element("xml").Element("return_code").Value;

            Hashtable hashtable = new Hashtable();

            hashtable.Add("return_code", return_code);

            return Json(hashtable);
        }