C# .net 微信扫码Native支付模式二以及成功回调

微信官方文档地址
SDK与DEMO下载

1. 修改 lib=》DemoConfig 基本信息

2. 配置二维码的参数 business=》NativePay.cs3. 返回链接生成二维码返回前端
   安装生成二维码的包

   ThoughtWorks.QRCode 
   

   生成二维码两种方式，流，图片

   //示例一
   public FileResult paymentInformation(){
            string pay = WxPayAPI.NativePay.GetPayUrl(out_trade_no,productId,total_fee, body, attach, goods_tag);
              //初始化二维码生成工具
              QRCodeEncoder qrCodeEncoder = new QRCodeEncoder();
              qrCodeEncoder.QRCodeEncodeMode = QRCodeEncoder.ENCODE_MODE.BYTE;
              qrCodeEncoder.QRCodeErrorCorrect = QRCodeEncoder.ERROR_CORRECTION.M;
              qrCodeEncoder.QRCodeVersion = 0;
              qrCodeEncoder.QRCodeScale = 4;
              //将字符串生成二维码图片 pay接口返回的url
              Bitmap image = qrCodeEncoder.Encode(pay, Encoding.Default);
              //保存为PNG到内存流 
              MemoryStream ms = new MemoryStream();
              image.Save(ms, ImageFormat.Png);
              //保存为PNG到内存流
              return File(ms.ToArray(), "image/png");
   }
   

   //示例二
   public void paymentInformation(){
          string pay = WxPayAPI.NativePay.GetPayUrl(out_trade_no,productId,total_fee, body, attach, goods_tag);
               //初始化二维码生成工具
               QRCodeEncoder qrCodeEncoder = new QRCodeEncoder();
               qrCodeEncoder.QRCodeEncodeMode = QRCodeEncoder.ENCODE_MODE.BYTE;
               qrCodeEncoder.QRCodeErrorCorrect = QRCodeEncoder.ERROR_CORRECTION.M;
               qrCodeEncoder.QRCodeVersion = 0;
               qrCodeEncoder.QRCodeScale = 4;
               //将字符串生成二维码图片
               Bitmap image = qrCodeEncoder.Encode(pay, Encoding.Default);
               //保存为PNG到内存流 
               MemoryStream ms = new MemoryStream();
               image.Save(ms, ImageFormat.Png);
               //输出二维码图片
               Response.BinaryWrite(ms.GetBuffer());
               Response.End();
   }
   

 public async Task PayNotifyUrl()
        {

            try
            {
                //接收从微信后台POST过来的数据
                Stream s = Request.InputStream;
                byte[] buffer = new byte[Request.InputStream.Length];
                await s.ReadAsync(buffer, 0, buffer.Length); /
                string xml = System.Text.Encoding.UTF8.GetString(buffer);
                XmlDocument xmlDoc = new XmlDocument();
                xmlDoc.LoadXml(xml);
                string return_code = xmlDoc.DocumentElement.GetElementsByTagName("return_code")[0].InnerText;
                string out_trade_no = xmlDoc.DocumentElement.GetElementsByTagName("out_trade_no")[0].InnerText;//商户订单号
                string transaction_id = xmlDoc.DocumentElement.GetElementsByTagName("transaction_id")[0].InnerText;//微信支付订单号
                string nonce_str = xmlDoc.DocumentElement.GetElementsByTagName("nonce_str")[0].InnerText;//随机字符串
                string total_fee = xmlDoc.DocumentElement.GetElementsByTagName("total_fee")[0].InnerText; //金额
                string attach = xmlDoc.DocumentElement.GetElementsByTagName("attach")[0].InnerText;
                //业务逻辑 
                
                //微信支付成功回调
                if (return_code.ToUpper() == "SUCCESS")
                {
                    return "";
                }
                else
                {
                    return ""; //回调失败返回给微信
                }
            }
            catch (Exception)
            {
               
                return ""; //回调失败返回给微信
            }
        }