支付宝小程序开发系列三： 统一下单支付（.net）

第一步：后台构造统一下单参数(SDK：https://download.csdn.net/download/qq_36894527/12875709)

/// 

        /// 支付宝统一下单接口
        /// 
        /// 
        /// 应用私钥
        /// 支付宝公钥
        /// user_id
        /// 
        /// 
        /// 
        public static string TradePay(string appid, string merchant_private_key ,string alipay_public_key,string notifyurl,string user_id, string total_fee, string bill)
        {
            decimal fee = decimal.Round(decimal.Parse(total_fee), 2);
            string result = "";
            try
            {
                IAopClient client = new DefaultAopClient("https://openapi.alipay.com/gateway.do", appid, merchant_private_key, "json", "1.0", "RSA2", alipay_public_key, "GBK", false);
                AlipayTradeCreateRequest request = new AlipayTradeCreateRequest();
                request.SetNotifyUrl(notifyUrl);
                request.BizContent = "{" +
                ""out_trade_no":"" + bill + ""," +
                //""seller_id":""," +
                ""total_amount":"" + fee + ""," +
                //""discountable_amount":0," +
                ""subject":"会员充值"," +
                //""body":"支付宝会员充值"," +
                ""buyer_id":"" + user_id+ """ +
                 //"      "goods_detail":[{" +
                 //"        "goods_id":"apple-01"," +
                 //""goods_name":"ipad"," +
                 //""quantity":1," +
                 //""price":2000," +
                 //""goods_category":"34543238"," +
                 //""categories_tree":"124868003|126232002|126252004"," +
                 //""body":"特价手机"," +
                 //""show_url":"http://www.alipay.com/xxx.jpg"" +
                 //"        }]," +
                 //""product_code":"FACE_TO_FACE_PAYMENT"," +
                 //""operator_id":"Yx_001"," +
                 //""store_id":"NJ_001"," +
                 //""terminal_id":"NJ_T_001"," +
                 //""extend_params":{" +
                 //""sys_service_provider_id":"2088511833207846"," +
                 //""card_type":"S0JP0000"" +
                 //"    }," +
                 //""timeout_express":"90m"," +
                 //""settle_info":{" +
                 //"        "settle_detail_infos":[{" +
                 //"          "trans_in_type":"cardAliasNo"," +
                 //""trans_in":"A0001"," +
                 //""summary_dimension":"A0001"," +
                 //""settle_entity_id":"2088xxxxx;ST_0001"," +
                 //""settle_entity_type":"SecondMerchant、Store"," +
                 //""amount":0.1" +
                 //"          }]," +
                 //""settle_period_time":"7d"" +
                 //"    }," +
                 //""logistics_detail":{" +
                 //""logistics_type":"EXPRESS"" +
                 //"    }," +
                 //""business_params":{" +
                 //""campus_card":"0000306634"," +
                 //""card_type":"T0HK0000"," +
                 //""actual_order_time":"2019-05-14 09:18:55"" +
                 //"    }," +
                 //""receiver_address_info":{" +
                 //""name":"张三"," +
                 //""address":"上海市浦东新区陆家嘴银城中路501号"," +
                 //""mobile":"13120180615"," +
                 //""zip":"200120"," +
                 //""division_code":"310115"" +
                 //"    }" +
                 "  }";
                AlipayTradeCreateResponse response = client.Execute(request);
                Console.WriteLine(response.Body);
                JObject jobj = (JObject)JsonConvert.DeserializeObject(response.Body);
                if (jobj["alipay_trade_create_response"]["code"].ToString() == "10000")
                {
                    string trade_no = jobj["alipay_trade_create_response"]["trade_no"].ToString();
                    result = ReturnInfo.CodeReturn("S",trade_no);
                }
                else
                {
                    string msg = jobj["alipay_trade_create_response"]["msg"].ToString();
                    result = ReturnInfo.CodeReturn("E", msg);
                }
            }
            catch (Exception ex)
            {
                result = ReturnInfo.CodeReturn("E", ex.Message);
            }
            return result;
        }

第二步：小程序发起支付

 my.tradePay({
            tradeNO: res,//后台返回的支付宝交易单号
            success: function (res) {}
});