public class Config
{
 // 应用ID,您的APPID
 public static string AppId = "";
 /// <summary>
 /// 合作商户uid
 /// </summary>
 public static string Uid = "";
 // 支付宝网关
 public static string Gatewayurl = "https://openapi.alipaydev.com/gateway.do";
 // 商户私钥，您的原始格式RSA私钥
 public static string PrivateKey = "";
 // 支付宝公钥,查看地址：https://openhome.alipay.com/platform/keyManage.htm 对应APPID下的支付宝公钥。
 public static string AlipayPublicKey = "";
 // 签名方式
 public static string SignType = "RSA2";
 // 编码格式
 public static string CharSet = "UTF-8";
}

/// <summary>
/// 生成支付二维码
/// </summary>
/// <param name="orderName">订单名称</param>
/// <param name="orderAmount">订单金额</param>
/// <param name="outTradeNo">订单号</param>
/// <returns></returns>
[HttpGet]
public IActionResult ScanCodeGen(string orderName, string orderAmount, string outTradeNo)
{
 AlipayTradePrecreateContentBuilder builder = BuildPrecreateContent(orderName,orderAmount,outTradeNo);
 //如果需要接收扫码支付异步通知，那么请把下面两行注释代替本行。
 //推荐使用轮询撤销机制，不推荐使用异步通知,避免单边账问题发生。
 AlipayF2FPrecreateResult precreateResult = _serviceClient.tradePrecreate(builder);
 //string notify_url = "http://10.5.21.14/Pay/Notify"; //商户接收异步通知的地址
 //AlipayF2FPrecreateResult precreateResult = serviceClient.tradePrecreate(builder, notify_url);
 //以下返回结果的处理供参考。
 //payResponse.QrCode即二维码对于的链接
 //将链接用二维码工具生成二维码打印出来，顾客可以用支付宝钱包扫码支付。
 var bitmap = new Bitmap(Path.Combine(_hostingEnvironment.WebRootPath, "images/error.png"));
 switch (precreateResult.Status)
 {
 case ResultEnum.SUCCESS:
  bitmap.Dispose();
  bitmap=RenderQrCode(precreateResult.response.QrCode);
  //轮询订单结果
  //根据业务需要，选择是否新起线程进行轮询
  ParameterizedThreadStart parStart = new ParameterizedThreadStart(LoopQuery);
  Thread myThread = new Thread(parStart);
  object o = precreateResult.response.OutTradeNo;
  myThread.Start(o);
  break;
 case ResultEnum.FAILED:
  Console.WriteLine("生成二维码失败："+ precreateResult.response.Body);
  break;
 case ResultEnum.UNKNOWN:
  Console.WriteLine("生成二维码失败：" + (precreateResult.response == null ? "配置或网络异常，请检查后重试" : "系统异常，请更新外部订单后重新发起请求"));
  break;
 }
 MemoryStream ms = new MemoryStream();
 bitmap.Save(ms, ImageFormat.Png);
 byte[] bytes = ms.GetBuffer();
 return File(bytes, "image/png");
}

/// <summary>
/// 构造支付请求数据
/// </summary>
/// <param name="orderName">订单名称</param>
/// <param name="orderAmount">订单金额</param>
/// <param name="outTradeNo">订单编号</param>
/// <returns>请求结果集</returns>
private AlipayTradePrecreateContentBuilder BuildPrecreateContent(string orderName,string orderAmount,string outTradeNo)
{
 //线上联调时，请输入真实的外部订单号。
 if (string.IsNullOrEmpty(outTradeNo))
 {
 outTradeNo = System.DateTime.Now.ToString("yyyyMMddHHmmss") + "0000" + (new Random()).Next(1, 10000).ToString();
 }
 AlipayTradePrecreateContentBuilder builder = new AlipayTradePrecreateContentBuilder();
 //收款账号
 builder.seller_id = Config.Uid;
 //订单编号
 builder.out_trade_no = outTradeNo;
 //订单总金额
 builder.total_amount = orderAmount;
 //参与优惠计算的金额
 //builder.discountable_amount = "";
 //不参与优惠计算的金额
 //builder.undiscountable_amount = "";
 //订单名称
 builder.subject = orderName;
 //自定义超时时间
 builder.timeout_express = "5m";
 //订单描述
 builder.body = "";
 //门店编号，很重要的参数，可以用作之后的营销
 builder.store_id = "test store id";
 //操作员编号，很重要的参数，可以用作之后的营销
 builder.operator_id = "test";
 //传入商品信息详情
 List<GoodsInfo> gList = new List<GoodsInfo>();
 GoodsInfo goods = new GoodsInfo();
 goods.goods_id = "goods id";
 goods.goods_name = "goods name";
 goods.price = "0.01";
 goods.quantity = "1";
 gList.Add(goods);
 builder.goods_detail = gList;
 //系统商接入可以填此参数用作返佣
 //ExtendParams exParam = new ExtendParams();
 //exParam.sysServiceProviderId = "20880000000000";
 //builder.extendParams = exParam;
 return builder;
}

/// <summary>
/// 渲染二维码
/// </summary>
/// <param name="str"></param>
/// <returns></returns>
private Bitmap RenderQrCode(string str)
{
 QRCodeGenerator.ECCLevel eccLevel = QRCodeGenerator.ECCLevel.L;
 using (QRCodeGenerator qrGenerator = new QRCodeGenerator())
 {
 using (QRCodeData qrCodeData = qrGenerator.CreateQrCode(str, eccLevel))
 {
  using (QRCode qrCode = new QRCode(qrCodeData))
  {
  Bitmap bp= qrCode.GetGraphic(20, Color.Black, Color.White,
   new Bitmap(Path.Combine(_hostingEnvironment.WebRootPath, "images/alipay.png")), 15);
  return bp;
  }
 }
 }
}

/// <summary>
/// 轮询支付结果
/// </summary>
/// <param name="o">订单号</param>
public void LoopQuery(object o)
{
 AlipayF2FQueryResult queryResult = new AlipayF2FQueryResult();
 int count = 100;
 int interval = 10000;
 string outTradeNo = o.ToString();
 for (int i = 1; i <= count; i++)
 {
 Thread.Sleep(interval);
 queryResult = _serviceClient.tradeQuery(outTradeNo);
 if (queryResult?.Status == ResultEnum.SUCCESS)
 {
  DoSuccessProcess(queryResult);
  return;
 }
 }
 DoFailedProcess(queryResult);
}
/// <summary>
/// 请添加支付成功后的处理
/// </summary>
private void DoSuccessProcess(AlipayF2FQueryResult queryResult)
{
 //支付成功，请更新相应单据
 Console.WriteLine("扫码支付成功：商户订单号 " + queryResult.response.OutTradeNo);
}
/// <summary>
/// 请添加支付失败后的处理
/// </summary>
private void DoFailedProcess(AlipayF2FQueryResult queryResult)
{
 //支付失败，请更新相应单据
 Console.WriteLine("扫码支付失败：商户订单号 " + queryResult.response.OutTradeNo);
}