微信开发遇到最复杂的就是支付了,无论V2还是V3。这篇文章将给出全套的V3版本JSAPI支付代码,包括预支付->支付->订单查询->通知->退款,其中前三步已经上线应用,退款只是简单测试了一下,大家要用的话需要谨慎。。。
一、预支付&支付
实际就是讲订单信息交给微信端,返回给我们一个预支付id(与V2app支付相似),支付时将预支付id交给微信处理。注意:预支付id 需存储,每个out_trade_no(我们自己的订单号)只能对应一个预支付id。代码奉上:(mvc demo 最后会一并发出)
1 public ActionResult Pay()
2 {
3 string code = "";//网页授权获得的code
4 string orderNo = ""; //文档中的out_trade_no
5 string description = ""; //商品描述
6 string totalFee = "1";//订单金额(单位:分)
7 string createIp = "127.0.0.1";
8 string notifyUrl = ""; //通知url
9 string openId = WeiXinHelper.GetUserOpenId(code);//通过网页授权code获取用户openid(或者之前有存储用户的openid 也可以直接拿来用)
10
11 //prepayid 只有第一次支付时生成,如果需要再次支付,必须拿之前生成的prepayid。
12 //也就是说一个orderNo 只能对应一个prepayid
13 string prepayid = string.Empty;
14
15 #region 之前生成过 prepayid,此处可略过
16
17 //创建Model
18 UnifiedWxPayModel model = UnifiedWxPayModel.CreateUnifiedModel(WeiXinConst.AppId, WeiXinConst.PartnerId, WeiXinConst.PartnerKey);
19
20 //预支付
21 UnifiedPrePayMessage result = WeiXinHelper.UnifiedPrePay(model.CreatePrePayPackage(description, orderNo, totalFee, createIp, notifyUrl, openId));
22
23 if (result == null
24 || !result.ReturnSuccess
25 || !result.ResultSuccess
26 || string.IsNullOrEmpty(result.Prepay_Id))
27 {
28 throw new Exception("获取PrepayId 失败");
29 }
30
31 //预支付订单
32 prepayid = result.Prepay_Id;
33
34 #endregion
35
36 //JSAPI 支付参数的Model
37 PayModel payModel = new PayModel()
38 {
39 AppId = model.AppId,
40 Package = string.Format("prepay_id={0}", prepayid),
41 Timestamp = ((DateTime.Now.ToUniversalTime().Ticks - 621355968000000000) / 10000000).ToString(),
42 Noncestr = CommonUtil.CreateNoncestr(),
43 };
44
45 Dictionary nativeObj = new Dictionary();
46 nativeObj.Add("appId", payModel.AppId);
47 nativeObj.Add("package", payModel.Package);
48 nativeObj.Add("timeStamp", payModel.Timestamp);
49 nativeObj.Add("nonceStr", payModel.Noncestr);
50 nativeObj.Add("signType", payModel.SignType);
51 payModel.PaySign = model.GetCftPackage(nativeObj); //生成JSAPI 支付签名
52
53
54 return View(payModel);
55 }
UnifiedWxPayModel 为V3统一支付帮助类,包括V3相关接口参数生成及签名的实现:

这里用到的 生成预支付请求参数Xml:
1 #region 生成 预支付 请求参数(XML) 2 ///3 /// 生成 预支付 请求参数(XML) 4 /// 5 /// 6 /// 7 /// 8 /// 9 /// 10 /// 11 ///12 public string CreatePrePayPackage(string description, string tradeNo, string totalFee, string createIp, string notifyUrl, string openid) 13 { 14 Dictionary nativeObj = new Dictionary (); 15 16 nativeObj.Add("appid", AppId); 17 nativeObj.Add("mch_id", PartnerId); 18 nativeObj.Add("nonce_str", CommonUtil.CreateNoncestr()); 19 nativeObj.Add("body", description); 20 nativeObj.Add("out_trade_no", tradeNo); 21 nativeObj.Add("total_fee", totalFee); //todo:写死为1 22 nativeObj.Add("spbill_create_ip", createIp); 23 nativeObj.Add("notify_url", notifyUrl); 24 nativeObj.Add("trade_type", "JSAPI"); 25 nativeObj.Add("openid", openid); 26 nativeObj.Add("sign", GetCftPackage(nativeObj)); 27 28 return DictionaryToXmlString(nativeObj); 29 } 30 31 #endregion
预支付请求在WeiXinHelper中,实现方式与前几篇中相似,这里就不上代码了。
二、订单查询
JSAPI返回支付成功,我们需要到后台查询下订单状态以确定支付是否成功,如果后台未接到通知,则要到微信服务器查询订单状态;最后才能展示给用户支付的结果:
1 ///2 /// 到微信服务器查询 订单支付的结果 (jsapi支付返回ok,我们要判断下服务器支付状态,如果没有支付成功,到微信服务器查询) 3 /// 4 /// 5 public bool QueryOrder(string orderNo) 6 { 7 //这里应先判断服务器 订单支付状态,如果接到通知,并已经支付成功,就不用 执行下面的查询了 8 UnifiedWxPayModel model = UnifiedWxPayModel.CreateUnifiedModel(WeiXinConst.AppId, WeiXinConst.PartnerId, WeiXinConst.PartnerKey); 9 UnifiedOrderQueryMessage message = WeiXinHelper.UnifiedOrderQuery(model.CreateOrderQueryXml(orderNo)); 10 //此处主动查询的结果,只做查询用(不能作为支付成功的依据) 11 return message.Success; 12 }
生成订单查询Xml方法:
#region 创建订单查询 XML
2 ///
3 /// 创建订单查询 XML
4 ///
5 ///
6 ///
7 public string CreateOrderQueryXml(string orderNo)
8 {
9 Dictionary nativeObj = new Dictionary();
10
11 nativeObj.Add("appid", AppId);
12 nativeObj.Add("mch_id", PartnerId);
13 nativeObj.Add("out_trade_no", orderNo);
14 nativeObj.Add("nonce_str", CommonUtil.CreateNoncestr());
15 nativeObj.Add("sign", GetCftPackage(nativeObj));
16
17 return DictionaryToXmlString(nativeObj);
18 }
19 #endregion
三、通知
微信支付通知以Post Xml方式:
1 ///ReturnMessage是调用V3接口返回消息基类,也包含了给微信返回消息的方法:2 /// 微信支付通知(貌似比较臃肿,待优化) 3 /// 4 ///5 public void Notify() 6 { 7 ReturnMessage returnMsg = new ReturnMessage() { Return_Code = "SUCCESS", Return_Msg = "" }; 8 string xmlString = GetXmlString(Request); 9 NotifyMessage message = null; 10 try 11 { 12 //此处应记录日志 13 message = HttpClientHelper.XmlDeserialize (xmlString); 14 15 #region 验证签名并处理通知 16 XmlDocument doc = new XmlDocument(); 17 doc.LoadXml(xmlString); 18 19 Dictionary dic = new Dictionary (); 20 string sign = string.Empty; 21 foreach (XmlNode node in doc.FirstChild.ChildNodes) 22 { 23 if (node.Name.ToLower() != "sign") 24 dic.Add(node.Name, node.InnerText); 25 else 26 sign = node.InnerText; 27 } 28 29 UnifiedWxPayModel model = UnifiedWxPayModel.CreateUnifiedModel(WeiXinConst.AppId, WeiXinConst.PartnerId, WeiXinConst.PartnerKey); 30 if (model.ValidateMD5Signature(dic, sign)) 31 { 32 //处理通知 33 } 34 else 35 { 36 throw new Exception("签名未通过!"); 37 } 38 39 #endregion 40 41 } 42 catch (Exception ex) 43 { 44 //此处记录异常日志 45 returnMsg.Return_Code = "FAIL"; 46 returnMsg.Return_Msg = ex.Message; 47 } 48 Response.Write(returnMsg.ToXmlString()); 49 Response.End(); 50 } 51 52 /// 53 /// 获取Post Xml数据 54 /// 55 /// 56 ///57 private string GetXmlString(HttpRequestBase request) 58 { 59 using (System.IO.Stream stream = request.InputStream) 60 { 61 Byte[] postBytes = new Byte[stream.Length]; 62 stream.Read(postBytes, 0, (Int32)stream.Length); 63 return System.Text.Encoding.UTF8.GetString(postBytes); 64 } 65 }
///
2 /// 消息基类
3 ///
4 public class ReturnMessage
5 {
6 [XmlElement("return_code")]
7 public string Return_Code { get; set; }
8
9 [XmlElement("return_msg")]
10 public string Return_Msg { get; set; }
11
12 public string ToXmlString()
13 {
14 return string.Format(@"
15 ", Return_Code, Return_Msg);
16 }
17 }
四、退款
退款需要用到证书,配置WeiXinConst内证书相关常量再使用:
///
2 /// 订单退款
3 ///
4 /// 微信交易单号
5 /// 我们自己的单号
6 /// 订单金额(分)
7 /// 退款单号(我们自己定义)
8 /// 退款金额(分)
9 ///
10 public bool UnifiedOrderRefund(string transaction_Id,string orderNo,string totalFee, string refundNo,string refundFee)
11 {
12 UnifiedWxPayModel model = UnifiedWxPayModel.CreateUnifiedModel(WeiXinConst.AppId, WeiXinConst.PartnerId, WeiXinConst.PartnerKey);
13 string postData = model.CreateOrderRefundXml(orderNo, transaction_Id, totalFee, refundNo, refundFee);
14 //退款需要用到证书, 要配置WeiXineConst CertPath 和 CertPwd
15 return WeiXinHelper.Refund(postData, WeiXinConst.CertPath, WeiXinConst.CertPwd);
16 }
创建订单退款Xml:
#region 创建订单退款 XML
2 ///
3 /// 创建订单退款 XML
4 ///
5 /// 商户订单号
6 /// 微信订单号
7 /// 总金额
8 /// 退款订单号
9 /// 退款金额
10 ///
11 public string CreateOrderRefundXml(string orderNo, string transactionId, string totalFee, string refundNo, string refundFee)
12 {
13 Dictionary nativeObj = new Dictionary();
14
15 nativeObj.Add("appid", AppId);
16 nativeObj.Add("mch_id", WeiXinConst.PartnerId);
17 nativeObj.Add("nonce_str", CommonUtil.CreateNoncestr());
18 if (string.IsNullOrEmpty(transactionId))
19 {
20 if (string.IsNullOrEmpty(orderNo))
21 throw new Exception("缺少订单号!");
22 nativeObj.Add("out_trade_no", orderNo);
23 }
24 else
25 {
26 nativeObj.Add("transaction_id", transactionId);
27 }
28
29 nativeObj.Add("out_refund_no", refundNo);
30 nativeObj.Add("total_fee", totalFee);
31 nativeObj.Add("refund_fee", refundFee);
32 nativeObj.Add("op_user_id", PartnerId); //todo:配置
33
34 nativeObj.Add("sign", GetCftPackage(nativeObj));
35
36 return DictionaryToXmlString(nativeObj);
37 }
38
39 #endregion
WeiXinHelper中V3退款方法:
1 #region V3 申请退款 2 3 ///4 /// 申请退款(V3接口) 5 /// 6 /// 请求参数 7 /// 证书路径 8 /// 证书密码 9 public static bool Refund(string postData, string certPath, string certPwd) 10 { 11 string url = WeiXinConst.WeiXin_Pay_UnifiedOrderRefundUrl; 12 RefundMessage message = RefundHelper.PostXmlResponse(url, postData, certPath, certPwd); 13 return message.Success; 14 } 15 16 #endregion
V3退款帮助类:
1 ///2 /// V3退款帮助类 3 /// 4 public class RefundHelper 5 { 6 ///7 /// 证书验证的 post请求 8 /// 9 ///10 /// 请求Url 11 /// post数据 12 /// 证书路径 13 /// 证书密码 14 /// 15 public static T PostXmlResponse (string url, string postData, string certPath, string certPwd) where T : class 16 { 17 if (url.StartsWith("https")) 18 System.Net.ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls; 19 20 HttpWebRequest hp = (HttpWebRequest)WebRequest.Create(url); 21 22 ServicePointManager.ServerCertificateValidationCallback = new RemoteCertificateValidationCallback(CheckValidationResult); 23 24 hp.ClientCertificates.Add(new X509Certificate2(certPath, certPwd)); 25 26 var encoding = System.Text.Encoding.UTF8; 27 byte[] data = encoding.GetBytes(postData); 28 29 hp.Method = "POST"; 30 31 hp.ContentType = "application/x-www-form-urlencoded"; 32 33 hp.ContentLength = data.Length; 34 35 using (Stream ws = hp.GetRequestStream()) 36 { 37 // 发送数据 38 ws.Write(data, 0, data.Length); 39 ws.Close(); 40 41 using (HttpWebResponse wr = (HttpWebResponse)hp.GetResponse()) 42 { 43 using (StreamReader sr = new StreamReader(wr.GetResponseStream(), encoding)) 44 { 45 return HttpClientHelper.XmlDeserialize (sr.ReadToEnd()); 46 } 47 } 48 } 49 } 50 51 //验证服务器证书 52 private static bool CheckValidationResult(object sender, X509Certificate certificate, X509Chain chain, SslPolicyErrors errors) 53 { 54 return true; 55 } 56 }
私有的方法:
- Dictionary
转为XmlDocument 1 ///
2 /// dictionary转为xml 字符串 3 /// 4 /// 5 ///6 private static string DictionaryToXmlString(Dictionary dic) 7 { 8 StringBuilder xmlString = new StringBuilder(); 9 xmlString.Append(" "); 10 foreach (string key in dic.Keys) 11 { 12 xmlString.Append(string.Format("<{0}>{0}>", key, dic[key])); 13 } 14 xmlString.Append(" "); 15 return xmlString.ToString(); 16 }
- XmlDocument转为DictionaryView Code
1 ///
2 /// xml字符串 转换为 dictionary 3 /// 4 /// 5 ///6 public static Dictionary XmlToDictionary(string xmlString) 7 { 8 System.Xml.XmlDocument document = new System.Xml.XmlDocument(); 9 document.LoadXml(xmlString); 10 11 Dictionary dic = new Dictionary (); 12 13 var nodes = document.FirstChild.ChildNodes; 14 15 foreach (System.Xml.XmlNode item in nodes) 16 { 17 dic.Add(item.Name, item.InnerText); 18 } 19 return dic; 20 }





