需求
在招聘报名系统里，考务费支付是其中一个环节，支付方式很多种，比如银联、微信、支付宝等等。本次我们以微信支付进行举例，在考生注册账号、编写简历、报名职位、被初审核通过等一系列基础的条件的具备下，可以进入支付考务费的环节（笔试费用），我们会为其生成一个支付二维码，考生支付后（无论成功与否），都会记录其支付结果状态。
在实际的应用中，对于支付成功的考生，我们会遇到实现退款的需求，只要包括如下场景：
1、根据政策规定，某些符合全部或部分退款条件的考生。
2、其它未知原因，重复支付订单的考生。
3、其它不可抗力，需求进行退款的考生。
基础准备
在实现功能前，做为企业，我们需要申请一个微信服务号，并成为微信支付商家。
1、申请服务号
申请成功后会获得到 AppId 和 AppSecret 用于后续开发，如关联支付商户、网页授权登录等。
具体指引请参照微信公众平台首页：
2、成为微信支付商家
申请成功后会获得 Mchid 和 paySignKey 用于微信支付、退款等，请在商家后台务必关联申请的公众号。
具体指引请参照微信支付平台首页：
上述两个平台申请成功后，请登录微信支付商家平台，进行如下图操作：
在产品中心、AppID帐号管理、关联 AppID（即申请的服务号）
另外一个重要配置是支付目录，我们写的支付程序需要在这里设置，如下图：
关键代码
操作界面
界面上会显示最近一笔的微信订单支付情况，包括订单号、交费时间、交费金额、退款金额。其中退款金额不能大于成功交费金额，否则会返回失败。另外，还可以显示微信交易跟踪日志列表信息，如果订单号、交易价格、openid、返回信息、交易状态等。
示例界面如下：
退款订单类及方法
实现微信退款，需要在支付商家平台申请退款证书，证书文件保存到自定义的目录中，在退款时指定路径。
退款示例代码如下：
const string RefundOrderUrl = "https://api.mch.weixin.qq.com/secapi/pay/refund"; //退款申请API地址 const string RefundQueryUrl = "https://api.mch.weixin.qq.com/pay/refundquery"; //退款查询API地址 //退款订单明细类 public class RefundOrderDetail { /// <summary> /// 返回状态码，SUCCESS/FAIL 此字段是通信标识，非交易标识，交易是否成功需要查看trade_state来判断 /// </summary> public string return_code = ""; /// <summary> /// 返回信息返回信息，如非空，为错误原因 签名失败 参数格式校验错误 /// </summary> public string return_msg = ""; /// <summary> /// 业务结果,SUCCESS/FAIL /// </summary> public string result_code = ""; /// <summary> /// 错误代码 /// </summary> public string err_code = ""; /// <summary> /// 错误代码描述 /// </summary> public string err_code_des = ""; /// <summary> /// 公众号ID(微信分配的公众账号 ID) /// </summary> public string appid = ""; /// <summary> /// 商户号(微信支付分配的商户号) /// </summary> public string mch_id = ""; /// <summary> /// 微信支付分配的终端设备号 /// </summary> public string device_info = ""; /// <summary> /// 随机字符串，不长于32位 /// </summary> public string nonce_str = ""; /// <summary> /// 签名 /// </summary> public string sign = ""; /// <summary> /// 微信支付订单号 /// </summary> public string transaction_id = ""; /// <summary> /// 商户系统的订单号，与请求一致。 /// </summary> public string out_trade_no = ""; public string out_refund_no = ""; public string refund_id = ""; public string refund_fee = ""; public string settlement_refund_fee = ""; /// <summary> /// 订单总金额，单位为分 /// </summary> public string total_fee = ""; /// </summary> public string settlement_total_fee = ""; public string fee_type = ""; public string cash_fee = ""; public string cash_fee_type = ""; public string cash_refund_fee = ""; public string coupon_type_0 = ""; public string coupon_refund_fee = ""; public string coupon_refund_fee_0 = ""; public string coupon_refund_count = ""; public string coupon_refund_id_0 = ""; } //退款订单类 public class RefundOrder { /// <summary> /// 公众号ID(微信分配的公众账号 ID) /// </summary> public string appid = ""; /// <summary> /// 商户号(微信支付分配的商户号) /// </summary> public string mch_id = ""; /// <summary> /// 微信支付分配的终端设备号 /// </summary> public string device_info = ""; /// <summary> /// 随机字符串，不长于 32 位 /// </summary> public string nonce_str = ""; /// <summary> /// 签名 public string sign = ""; public string sign_type = ""; /// <summary> /// 商户系统内部的订单号,32个字符内、可包含字母,确保在商户系统唯一,详细说明 /// </summary> public string transaction_id = ""; public string out_trade_no = ""; public string out_refund_no = ""; /// <summary> /// 订单总金额，单位为分，不能带小数点 /// </summary> public int total_fee = 0; public int refund_fee = 0; public string refund_fee_type = ""; public string op_user_id = ""; /// <summary> public string refund_account = ""; /// <summary> } //查询对帐订单类 public class QueryOrder { /// <summary> /// 公共号ID(微信分配的公众账号 ID) /// </summary> public string appid = ""; /// <summary> /// 商户号(微信支付分配的商户号) /// </summary> public string mch_id = ""; /// <summary> /// 微信订单号，优先使用 /// </summary> public string transaction_id = ""; /// <summary> /// 商户系统内部订单号 /// </summary> public string out_trade_no = ""; /// <summary> /// 随机字符串，不长于 32 位 /// </summary> public string nonce_str = ""; /// <summary> /// 签名，参与签名参数：appid，mch_id，transaction_id，out_trade_no，nonce_str，key /// </summary> public string sign = ""; } //申请退款方法，返回退款订单明细类 //参数refundorder为退款订单类, key 为支付签名KEY,cert为证书地址,password 为证书密码 public RefundOrderDetail getRefundOrderDetail(RefundOrder refundorder, string key,string cert,string password) { string post_data = getRefundOrderXml(refundorder, key); string request_data = PostXmlAndCertToUrl(RefundOrderUrl, post_data,cert,password); RefundOrderDetail orderdetail = new RefundOrderDetail(); SortedDictionary<string, string> requestXML = GetInfoFromXml(request_data); foreach (KeyValuePair<string, string> k in requestXML) { switch (k.Key) { case "retuen_code": orderdetail.result_code = k.Value; break; case "return_msg": orderdetail.return_msg = k.Value; break; case "result_code": orderdetail.result_code = k.Value; break; case "err_code": orderdetail.err_code = k.Value; break; case "err_code_des": orderdetail.err_code_des = k.Value; break; case "appid": orderdetail.appid = k.Value; break; case "mch_id": orderdetail.mch_id = k.Value; break; case "device_info": orderdetail.device_info = k.Value; break; case "nonce_str": orderdetail.nonce_str = k.Value; break; case "sign": orderdetail.sign = k.Value; break; case "transaction_id": orderdetail.transaction_id = k.Value; break; case "out_trade_no": orderdetail.out_trade_no = k.Value; break; case "out_refund_no": orderdetail.out_refund_no = k.Value; break; case "refund_id": orderdetail.refund_id = k.Value; break; case "refund_fee": orderdetail.refund_fee = k.Value; break; case "total_fee": orderdetail.total_fee = k.Value; break; case "settlement_refund_fee": orderdetail.settlement_refund_fee = k.Value; break; case "settlement_total_fee": orderdetail.settlement_total_fee = k.Value; break; case "fee_type": orderdetail.fee_type = k.Value; break; case "cash_fee": orderdetail.cash_fee = k.Value; break; case "cash_fee_type ": orderdetail.cash_fee_type = k.Value; break; case "cash_refund_fee": orderdetail.cash_refund_fee = k.Value; break; case "coupon_type_0": orderdetail.coupon_type_0 = k.Value; break; case "coupon_refund_fee": orderdetail.coupon_refund_fee = k.Value; break; case "coupon_refund_fee_0": orderdetail.coupon_refund_fee_0 = k.Value; break; case "coupon_refund_count": orderdetail.coupon_refund_count = k.Value; break; case "coupon_refund_id_0": orderdetail.coupon_refund_id_0 = k.Value; break; default: break; } } return orderdetail; } protected string getRefundOrderXml(RefundOrder refundorder, string key) { string return_string = string.Empty; SortedDictionary<string, string> sParams = new SortedDictionary<string, string>(); sParams.Add("appid", refundorder.appid); sParams.Add("mch_id", refundorder.mch_id); // sParams.Add("transaction_id", refundorder.transaction_id); sParams.Add("out_trade_no", refundorder.out_trade_no); sParams.Add("nonce_str", refundorder.nonce_str); sParams.Add("out_refund_no", refundorder.out_refund_no); sParams.Add("total_fee", refundorder.total_fee.ToString()); sParams.Add("refund_fee", refundorder.refund_fee.ToString()); sParams.Add("op_user_id", refundorder.op_user_id); refundorder.sign = getsign(sParams, key); sParams.Add("sign", refundorder.sign); //拼接成XML请求数据 StringBuilder sbPay = new StringBuilder(); foreach (KeyValuePair<string, string> k in sParams) { if (k.Key == "attach" || k.Key == "body" || k.Key == "sign") { sbPay.Append("<" + k.Key + "><![CDATA[" + k.Value + "]]></" + k.Key + ">"); } else { sbPay.Append("<" + k.Key + ">" + k.Value + "</" + k.Key + ">"); } } return_string = string.Format("<xml>{0}</xml>", sbPay.ToString().TrimEnd(',')); return return_string; } public string PostXmlAndCertToUrl(string url, string postData,string cert,string password) { string resp = string.Empty; ServicePointManager.ServerCertificateValidationCallback = new System.Net.Security.RemoteCertificateValidationCallback(CheckValidationResult); //调用证书 System.Security.Cryptography.X509Certificates.X509Certificate2 cer = new System.Security.Cryptography.X509Certificates.X509Certificate2(cert, password, System.Security.Cryptography.X509Certificates.X509KeyStorageFlags.PersistKeySet | System.Security.Cryptography.X509Certificates.X509KeyStorageFlags.MachineKeySet); HttpWebRequest webrequest = (HttpWebRequest)HttpWebRequest.Create(url); webrequest.ClientCertificates.Add(cer); webrequest.Method = "post"; webrequest.ContentType = "application/x-www-form-urlencoded"; webrequest.ContentLength = postData.Length; //webrequest.ContentType = "text/xml"; //byte[] data = System.Text.Encoding.UTF8.GetBytes(postData); //webrequest.ContentLength = data.Length; HttpWebResponse response = null; try { StreamWriter swRequestWriter = new StreamWriter(webrequest.GetRequestStream()); swRequestWriter.Write(postData); if (swRequestWriter != null) swRequestWriter.Close(); response = (HttpWebResponse)webrequest.GetResponse(); using (StreamReader reader = new StreamReader(response.GetResponseStream(), Encoding.UTF8)) { resp = reader.ReadToEnd(); } } catch (Exception exp) { throw exp; } finally { if (response != null) response.Close(); } return resp; } public string getNoncestr() { Random random = new Random(); return GetMD5(random.Next(1000).ToString(), "GBK").ToLower().Replace("s", "S"); }
退款功能实现
假设点击退款按钮事件
protected void Button_Click(object sender, EventArgs e) { string appId = “”； //服务号的appId string paySignKey = “”； //申请的支付签名KEY; string mch_id = “”; //申请的支付商户ID string OrderID = ""; //支付订单号 string OrderAmount = (Convert.ToInt32((float.Parse(Amount.Text) * 100))).ToString(); //订单支付金额，Amount.Text 支付金额 string RefundOrderAmount = (Convert.ToInt32((float.Parse(Amount.Text) * 100))).ToString(); //退款金额（Amount.Text）这里表示全额退款 string RefundOrderID = Guid.NewGuid().ToString().Replace("-", ""); //生成退款订单号 //创建退款订单 RefundOrder order = new RefundOrder(); order.appid = appId; order.mch_id = mch_id; order.out_trade_no = OrderID; order.nonce_str = tenpay.getNoncestr(); order.out_refund_no = RefundOrderID; order.total_fee = int.Parse(OrderAmount); order.refund_fee = int.Parse(RefundOrderAmount); order.op_user_id = mch_id; string cert = “d:\\apiclient_cert.p12"; //退款证书路径 //私钥（在安装证书时设置） string password =""; //证书密码 //创建订单明细类，调用getRefundOrderDetail方法进行退款 RefundOrderDetail orderdetail = getRefundOrderDetail(order, paySignKey, cert, password); string rv = ("退款订单号:" + RefundOrderID + "<br>"); try { rv += ("退款金额:" + (double.Parse(orderdetail.total_fee) / 100).ToString() + "<br>"); } catch (Exception eee) { rv += ("退款金额:<br>"); } rv += ("<b>交易状态: " + (orderdetail.result_code == "SUCCESS" ? "退款申请成功" : "退款申请失败") + "(" + orderdetail.result_code + ")" + "</b><br>"); rv += ("可能的错误描述:" + orderdetail.err_code_des); }
对帐
退款申请成功后，仅为申请状态，需要通过查询退款情况以确定是否完成，该功能可以在考生方进行实现，考生可随时查询自己的对帐情况。
以下是参考代码，该代码可实现支付与退款的查询：
protected void queryOrder(object sender, EventArgs e) { string OrderID =”“; //订单号 string paytype = ”“； //查询类型，支付消费或退款 string appId = ""; //服务号 appid string paySignKey = ""; //支付签名key string mch_id = ""; //支付商户号 if (paytype == "消费") { try { string openid = ”“; QueryOrder order = new QueryOrder(); order.appid = appId; order.mch_id = mch_id; order.out_trade_no = OrderID; order.nonce_str = getNoncestr(); OrderDetail orderdetail = getOrderDetail(order, paySignKey); string rv = ("订单号:" + OrderID + "<br>"); rv += ("付款人ID比对识别:" + (openid == orderdetail.openid ? "成功" : "失败") + "<br>"); rv += ("交易金额:" + (double.Parse(orderdetail.total_fee) / 100).ToString() + "<br>"); rv += ("<b>交易状态: " + (orderdetail.trade_state == "SUCCESS" ? "成功" : "失败") + "(" + orderdetail.trade_state + ")" + "</b><br>"); rv += ("支付交易时间:" + (orderdetail.time_end != "" && orderdetail.time_end.Length == 14 ? orderdetail.time_end.Substring(0, 4) + "-" + orderdetail.time_end.Substring(4, 2) + "-" + orderdetail.time_end.Substring(6, 2) + " " + orderdetail.time_end.Substring(8, 2) + ":" + orderdetail.time_end.Substring(10, 2) + ":" + orderdetail.time_end.Substring(12, 2) : "") + "<br>"); } catch (Exception ex) { return; } } else if (paytype == "退款") { try { RefundOrder order = new RefundOrder(); order.appid = appId; order.mch_id = mch_id; order.out_trade_no = OrderID; order.nonce_str = getNoncestr(); RefundOrderDetail orderdetail = getRefundQueryOrderDetail(order, paySignKey); string rv = ("<b>交易状态: " + (orderdetail.result_code == "SUCCESS" ? "成功" : "失败") + "(" + orderdetail.result_code + ")" + "</b><br>"); rv += ("其它说明:" + orderdetail.err_code_des); } catch (Exception ex) { } } }
支付商家后台相关要点
实时交易帐单查询
登录后台后，该操作可以进行实时交易的帐单对帐功能，以备在争议的时候进行查询，基本操作如下图：
点击交易中心、交易订单、批量订单查询、查询即可下载EXCEL格式的订单。
精确交易帐单查询
登录后台后，可查询精确交易帐单，该帐单每天10：00更新前一天的数据交易，我们可以进行CSV格式的下载，操作如下图：
点击交易中心、交易帐单、打包下载即可，请注意图中圈注的提示。
小结
以上提供的代码仅供参考，在实际的应用中，我们还可以根据业务需要编写其它功能，如下载微信官方对帐单，导入到应用系统中，与业务数据进行对帐，以排查争议数据；查询订单结果状态以更新业务争议状态信息等。
以上就是自己的一些分享，时间仓促，不妥之处还请大家批评指正！
