关于微信h5支付实例

流程

1. 配置请求参数
2. 请求下单接口
3. h5支付时，获取下单返回的mweb_url路径
4. 前端获取接口返回的url，请求此路径（手机访问前端界面，pc访问报错：商家格式配置错误）

适用场景

h5网站内，调用微信支付。

前端实例

	<script src="https://cdn.bootcss.com/jquery/3.4.1/jquery.min.js"></script>
		<script type="text/javascript">

 function pay() {
	$.ajax({
                async: false,
                cache: false,
                type: 'POST',
                url: "https://ztcapi.yzsheng.com/Try/WeChatIndex", //请求的action路径
                success: function (data) { 
alert(data.item);       
                window.location.href = data.item;
        },
error: function(XMLHttpRequest, textStatus, errorThrown) {
             console.log(XMLHttpRequest.status);
             console.log(XMLHttpRequest.readyState);
             console.log(textStatus);
        }
                
            });
        };
		</script>

后端C#实例

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Net;
using System.Security.Cryptography;
using System.Text;
using System.Web;
using System.Xml.Linq;

namespace WebApplication1.Common.PayHelper
{
    /// 

    /// H5微信支付封装
    /// 
    public static class H5PayHepler
    {
        static string _pre_order_url = "https://api.mch.weixin.qq.com";//请求域名

        static string _appid = "";//公众账号ID
        static string _mch_id = "";//商户号
        static string _partnerKey = "";//商家私钥，在微信支付中设置


        /// 

        /// H5微信支付
        /// 
        /// 
        #region 微信支付
        public static string WeChatIndex()
        {
            #region 下单
            var _attach = "支付测试";
            var _body = "H5支付测试";
            var _nonce_str = CreateNonce_str(); //随机字符串
            var _notify_url = ""; //回调地址
            var _out_trade_no = Guid.NewGuid().ToString("N"); //订单号
            var _spbill_create_ip = GetWebClientIp(); //终端ip
            var _total_fee = 0.01;//元为单位
            var _scene_info = $@"{{""h5_info"": {{""type"":""Wap"",""wap_url"": ""{_notify_url}"",""wap_name"": ""{_body}""}}}}"; //场景参数
            var _time_start = DateTime.Now.ToString("yyyyMMddHHmmss"); //请求开始时间
            var _time_expire = DateTime.Now.AddHours(1).ToString("yyyyMMddHHmmss"); //请求结束时间
            var _trade_type = "MWEB"; //请求类型
            var pre_order_httpResult = UnifiedOrder(_appid, _attach, _body, _mch_id, _nonce_str, _notify_url, _out_trade_no, _spbill_create_ip, _total_fee,
    _trade_type, _scene_info, _time_start, _time_expire); //下单
            var pre_order_resultStr = XElement.Parse(pre_order_httpResult);
            var pre_order_result_code = pre_order_resultStr.Element("return_code").Value;
            var pre_order_result_msg = pre_order_resultStr.Element("return_msg").Value;
            if (pre_order_result_code == "SUCCESS")
            {
                var pre_order_result_mweb_url = pre_order_resultStr.Element("mweb_url").Value;
                return pre_order_result_mweb_url;
            }
            #endregion
            return string.Empty;
        }
       
        /// 

        /// 下单
        /// 
        /// 公众账号ID
        /// 附加数据，在查询API和支付通知中原样返回，该字段主要用于商户携带订单的自定义数据
        /// String(32) 商品描述 商品或支付单简要描
        /// 商户号
        /// 随机字符串
        /// 接收微信支付异步通知回调地址,不可带参,与下面的Notify对应，开发者可自定义其他url地址 
        /// 商户系统内部的订单号,32个字符内、可包含字母
        /// 终端ip
        /// 收钱总额  分为单位 前台传过来后需要处理成分
        /// 交易类型H5支付的交易类型为MWEB
        /// 场景信息 WAP网站应用{"h5_info": {"type":"Wap","wap_url": "https://pay.qq.com","wap_name": "腾讯充值"}}
        /// 交易起始时间
        /// 交易结束时间
        /// 
        static string UnifiedOrder(string appid, string attach, string body, string mch_id, string nonce_str, string notify_url, string out_trade_no,
            string spbill_create_ip, double total_fee, string trade_type, string scene_info, string time_start, string time_expire)
        {
            var stringADict = new Dictionary<string, string>();
            stringADict.Add("appid", appid);
            stringADict.Add("attach", attach);
            stringADict.Add("body", body);
            stringADict.Add("mch_id", mch_id);
            stringADict.Add("nonce_str", nonce_str);
            stringADict.Add("notify_url", notify_url);
            stringADict.Add("out_trade_no", out_trade_no);
            stringADict.Add("spbill_create_ip", spbill_create_ip);
            stringADict.Add("total_fee", Math.Round(Convert.ToDecimal(total_fee) * 100, 0).ToString());//元转分
            stringADict.Add("trade_type", trade_type);
            stringADict.Add("scene_info", scene_info);
            stringADict.Add("time_start", time_start);
            stringADict.Add("time_expire", time_expire);
            var sign = Sign(stringADict, _partnerKey);//生成签名字符串  

            //组合xml内容
            StringBuilder strBuilder = new StringBuilder();
            strBuilder.Append("");
            strBuilder.Append($"{appid}");//公众号id  
            strBuilder.Append($"{attach}");//附加数据
            strBuilder.Append($"{body}");//商品描述
            strBuilder.Append($"{mch_id}");//商户号  
            strBuilder.Append($"{nonce_str}");//随机字符串  
            strBuilder.Append($"{notify_url}");//接收微信支付异步通知回调地址,不可带参,与下面的Notify对应，开发者可自定义其他url地址  
            strBuilder.Append($"{out_trade_no}");//商户系统内部的订单号,32个字符内、可包含字母  
            strBuilder.Append($"{spbill_create_ip}");//终端ip  
            strBuilder.Append($"{Math.Round(Convert.ToDecimal(total_fee) * 100, 0).ToString()}");//收钱总额  分为单位 前台传过来后需要处理成分  
            strBuilder.Append($"{trade_type}");//交易类型H5支付的交易类型为MWEB  
            strBuilder.Append($"{scene_info}");
            strBuilder.Append($"{time_start}");//交易起始时间
            strBuilder.Append($"{time_expire}");//交易结束时间
            strBuilder.Append($"{sign}");
            strBuilder.Append("");

            //var url = _pre_order_url + "/sandboxnew/pay/unifiedorder";//沙箱
            var url = _pre_order_url + "/pay/unifiedorder";
            var pre_order_httpResult = HttpPostRequestXml(url, strBuilder);
            return pre_order_httpResult;
        }
        /// 

        /// 查询订单
        /// 
        /// 公众账号ID
        /// 商户号
        /// 商户系统内部的订单号或微信的订单号
        /// 随机字符串
        /// 
        static string Orderquery(string appid, string mch_id, string out_trade_no, string nonce_str)
        {
            var stringADict = new Dictionary<string, string>();
            stringADict.Add("appid", appid);
            stringADict.Add("mch_id", mch_id);
            stringADict.Add("out_trade_no", out_trade_no);
            stringADict.Add("nonce_str", nonce_str);
            var sign = Sign(stringADict, _partnerKey);//生成签名字符串  

            //组合xml内容
            StringBuilder strBuilder = new StringBuilder();
            strBuilder.Append("");
            strBuilder.Append($"{appid}");
            strBuilder.Append($"{mch_id}");
            strBuilder.Append($"{out_trade_no}");
            strBuilder.Append($"{nonce_str}");
            strBuilder.Append($"{sign}");
            strBuilder.Append("");

            var url = _pre_order_url + "/pay/orderquery";
            var pre_order_httpResult = HttpPostRequestXml(url, strBuilder);
            return pre_order_httpResult;
        }

        /// 

        /// 发送post xml文件请求
        /// 
        /// 
        /// 
        /// 
        static string HttpPostRequestXml(string Url, StringBuilder strBuilder)
        {
            string result = string.Empty;
            string data = strBuilder.ToString();
            //进行utf-8编码
            var encoding = Encoding.GetEncoding("utf-8");
            byte[] buffer = encoding.GetBytes(data);
            //根据webURL创建HttpWebRequest对象
            HttpWebRequest request = (HttpWebRequest)WebRequest.Create(Url);
            request.Method = "post";
            //request.Headers.Add("charset:utf-8");            
            request.ContentLength = buffer.Length;
            request.ContentType = "text/xml";

            StreamWriter myWriter = null;
            try
            {
                myWriter = new StreamWriter(request.GetRequestStream());
                myWriter.Write(data);
            }
            catch (Exception e)
            {
                Console.WriteLine(e.Message);
            }
            finally
            {
                myWriter.Close();
            }
            //读取服务器返回的信息
            HttpWebResponse objResponse = (HttpWebResponse)request.GetResponse();
            using (StreamReader sr = new StreamReader(objResponse.GetResponseStream()))
            {
                result = sr.ReadToEnd();
            }
            return result;
        }

        private static string[] strs = new string[]
                                 {
                                  "a","b","c","d","e","f","g","h","i","j","k","l","m","n","o","p","q","r","s","t","u","v","w","x","y","z",
                                  "A","B","C","D","E","F","G","H","I","J","K","L","M","N","O","P","Q","R","S","T","U","V","W","X","Y","Z"
                                 };

        /// 
  
        /// 创建随机字符串  
        /// 
  
        ///   
        public static string CreateNonce_str()
        {
            Random r = new Random();
            var sb = new StringBuilder();
            var length = strs.Length;
            for (int i = 0; i < 15; i++)
            {
                sb.Append(strs[r.Next(length - 1)]);
            }
            return sb.ToString();
        }

        /// 
  
        /// 获取终端IP地址  
        /// 
  
        ///   
        public static string GetWebClientIp()
        {
            string userIP = "";
            try
            {
                if (System.Web.HttpContext.Current == null
            || System.Web.HttpContext.Current.Request == null
            || System.Web.HttpContext.Current.Request.ServerVariables == null)
                    return "";
                string CustomerIP = "";
                //CDN加速后取到的IP simone 090805  
                CustomerIP = System.Web.HttpContext.Current.Request.Headers["Cdn-Src-Ip"];
                if (!string.IsNullOrEmpty(CustomerIP))
                {
                    return CustomerIP;
                }
                CustomerIP = System.Web.HttpContext.Current.Request.ServerVariables["HTTP_X_FORWARDED_FOR"];
                if (!String.IsNullOrEmpty(CustomerIP))
                {
                    return CustomerIP;
                }
                if (System.Web.HttpContext.Current.Request.ServerVariables["HTTP_VIA"] != null)
                {
                    CustomerIP = System.Web.HttpContext.Current.Request.ServerVariables["HTTP_X_FORWARDED_FOR"];
                    if (CustomerIP == null)
                        CustomerIP = System.Web.HttpContext.Current.Request.ServerVariables["REMOTE_ADDR"];
                }
                else
                {
                    CustomerIP = System.Web.HttpContext.Current.Request.ServerVariables["REMOTE_ADDR"];
                }
                if (string.Compare(CustomerIP, "unknown", true) == 0)
                    return System.Web.HttpContext.Current.Request.UserHostAddress;
                return CustomerIP;
            }
            catch { }
            return userIP;
        }

        /// 
  
        /// 生成签名  
        /// 签名在线验证工具：  
        /// http://mch.weixin.qq.com/wiki/tools/signverify/  
        /// 
  
        /// 参与签名生成的参数列表  
        /// 商家私钥  
        ///   
        public static string Sign(IDictionary<string, string> stringADict, string partnerKey)
        {
            var sb = new StringBuilder();
            foreach (var sA in stringADict.OrderBy(x => x.Key))//参数名ASCII码从小到大排序（字典序）；  
            {
                if (string.IsNullOrEmpty(sA.Value)) continue;//参数的值为空不参与签名；  
                if (string.Compare(sA.Key, "sign", true) == 0) continue;    // 参数中为签名的项，不参加计算  
                sb.Append(sA.Key).Append("=").Append(sA.Value).Append("&");
            }
            var string1 = sb.ToString();
            string1 = string1.Remove(string1.Length - 1, 1);
            sb.Append("key=").Append(partnerKey);//在stringA最后拼接上key=(API密钥的值)得到stringSignTemp字符串  
            var stringSignTemp = sb.ToString();
            var sign = MD5Encrypt(stringSignTemp, "UTF-8").ToUpper();//对stringSignTemp进行MD5运算，再将得到的字符串所有字符转换为大写，得到sign值signValue。   
            return sign;
        }

        /// 

        /// 用MD5加密字符串
        /// 
        /// 待加密的字符串
        /// 
        public static string MD5Encrypt(string password, string encoding)
        {
            MD5CryptoServiceProvider md5Hasher = new MD5CryptoServiceProvider();
            byte[] hashedDataBytes;
            hashedDataBytes = md5Hasher.ComputeHash(Encoding.GetEncoding(encoding).GetBytes(password));
            StringBuilder tmp = new StringBuilder();
            foreach (byte i in hashedDataBytes)
            {
                tmp.Append(i.ToString("x2"));
            }
            return tmp.ToString();
        }
        #endregion
    }
}

注：部分转载于CSDN论坛，部分为自己研究所写