微信小程序支付功能 C# .NET开发

微信小程序支付功能的开发的时候坑比较多，不过对于钱的事谨慎也是好事。网上关于小程序支付的实例很多，但是大多多少有些问题，c#开发的更少。此篇文档的目的是讲开发过程中遇到的问题做一个备注，也方便其他开发的同学作为参考！

 

       1、首先建议把官方文档支付部分看上三遍，每个细节都不要放过，因为任何一个点和微信要求不符都会导致支付不成功。https://pay.weixin.qq.com/wiki/doc/api/wxa/wxa_api.php?chapter=3_1

      2、经过验证的微信支付功能，会需要一些商户号、支付秘钥等，不要搞混。

     3、经常遇到的是“签名错误”，请仔细看需要传送的xml参数及取值规则是否符合微信规则。微信有个验证工具可以验证发送的xml字段是否合法。

 

下面上代码：

 

web.config

 

    <add key="connectionstring" value="server=127.0.0.1;database=;uid=sa;pwd="/>
    <add key="connectionstring2" value="server=127.0.0.1;database=codematic2;uid=sa;pwd=1"/>
    <add key="appid" value=""/>//appid
    <add key="secret" value=""/>//小程序秘钥
    <add key="mch_id" value=""/>//商户号
    <add key="key" value=""/>//支付秘钥
    <add key="ip" value=""/>//服务器ip
    <add key="payresulturl" value=""/>//微信返回接收信息的url地址
  </appsettings>

支付后台xiadan.ashx

 

 

<%@ webhandler language="c#" class="xiadan" %>

using system;
using system.web;
using system.net;
using system.io;
using system.configuration;
using maticsoft.model;
using maticsoft.bll;
using system.security.cryptography;
using system.text;
using system.xml.serialization;
using system.xml;
using system.collections.generic;
using system.data;
using system.net.security;
using system.security.cryptography.x509certificates;
using system.linq;
using newtonsoft.json;

public class xiadan : ihttphandler
{

    public void processrequest(httpcontext context)
    {
        context.response.contenttype = "text/plain";
        string openid = context.request.params["openid"];
        string ordertime = context.request.params["ordertime"];

        string appid = configurationmanager.appsettings["appid"];
        string secret = configurationmanager.appsettings["secret"];
        string key = configurationmanager.appsettings["key"];
        string mch_id = configurationmanager.appsettings["mch_id"];
        string ip = configurationmanager.appsettings["ip"];
        string payresulturl = configurationmanager.appsettings["payresulturl"];
        string roomid = context.request.params["roomid"];
        string aa = "-押金";////商品描述交易字段格式根据不同的应用场景按照以下格式：app——需传入应用市场上的app名字-实际商品名称，天天爱消除-游戏充值。

        string strcode = aa;
        byte[] buffer = encoding.utf8.getbytes(strcode);
        string body = encoding.utf8.getstring(buffer, 0, buffer.length);
        string totalfee = context.request.params["totalfee"];
        string output = "";
        if ((context.request.params["openid"] != null) && (context.request.params["openid"] != ""))
        {
            //orderinfo order = new orderinfo();

            //order.appid = appid;

            system.random random = new system.random();



            var dic = new dictionary<string, string>
{
    {"appid", appid},
    {"mch_id", mch_id},
    {"nonce_str", getrandomstring(20)/*random.next().tostring()*/},
    {"body",body},
    {"out_trade_no",roomid + datetime.now.tostring("yyyymmddhhmmssfff") + random.next(999).tostring()},//商户自己的订单号码
    {"total_fee",totalfee},
    {"spbill_create_ip",ip},//服务器的ip地址
    {"notify_url",payresulturl},//异步通知的地址，不能带参数
    {"trade_type","jsapi" },
    {"openid",openid}
};
      //加入签名
            dic.add("sign", getsignstring(dic));

            var sb = new stringbuilder();
            sb.append("<xml>");


            foreach (var d in dic)
            {
                sb.append("<" + d.key + ">" + d.value + "</" + d.key + ">");
            }
            sb.append("</xml>");
            var xml = new xmldocument();
            //  xml.loadxml(getpoststring("https://api.mch.weixin.qq.com/pay/unifiedorder", sb.tostring()));
            cookiecollection coo = new cookiecollection();
            encoding en = encoding.getencoding("utf-8");

            httpwebresponse response = createposthttpresponse("https://api.mch.weixin.qq.com/pay/unifiedorder", sb.tostring(), en);
            //打印返回值
            stream stream = response.getresponsestream();   //获取响应的字符串流
            streamreader sr = new streamreader(stream); //创建一个stream读取流
            string html = sr.readtoend();   //从头读到尾，放到字符串html
                                            //console.writeline(html);
            xml.loadxml(html);
            //对请求返回值 进行处理

            var root = xml.documentelement;

            dataset ds = new dataset();
            stringreader stram = new stringreader(html);
            xmltextreader reader = new xmltextreader(stram);
            ds.readxml(reader);
            string return_code = ds.tables[0].rows[0]["return_code"].tostring();
            if (return_code.toupper() == "success")
            {
                //通信成功
                string result_code = ds.tables[0].rows[0]["result_code"].tostring();//业务结果
                if (result_code.toupper() == "success")
                {
                    var res = new dictionary<string, string>
{
    {"appid", appid},
    {"timestamp", gettimestamp()},
    {"noncestr", dic["nonce_str"]},
    {"package",  "prepay_id="+ds.tables[0].rows[0]["prepay_id"].tostring()},
    {"signtype", "md5"}
};

                    //在服务器上签名
                    res.add("paysign", getsignstring(res));
                    // string signapp = res.tostring();
                    string signapp = jsonconvert.serializeobject(res);
                    if ((context.request.params["openid"] != null) && (context.request.params["openid"] != ""))
                    { 
                    //存储订单信息
                    maticsoft.model.order_history oh = new maticsoft.model.order_history();
                    //oh.shop_id =
                    oh.room_id = convert.toint32(roomid);
                    oh.pay_price = convert.todecimal(totalfee);
                    oh.out_trade_no = dic["out_trade_no"];
                    oh.order_timestart = convert.todatetime(ordertime);
                    oh.openid = openid;
                    oh.creating_date = datetime.now;

                    maticsoft.bll.order_history bll = new maticsoft.bll.order_history();
                    bll.add(oh);

                }
                context.response.write(signapp);
            }
        }




    }
    context.response.write(output);
    }

public bool isreusable
{
    get
    {
        return false;
    }
}

public string getmd5hash(string input)
{
    if (input == null)
    {
        return null;
    }

    md5 md5hash = md5.create();

    // 将输入字符串转换为字节数组并计算哈希数据  
    byte[] data = md5hash.computehash(encoding.utf8.getbytes(input));

    // 创建一个 stringbuilder 来收集字节并创建字符串  
    stringbuilder sbuilder = new stringbuilder();

    // 循环遍历哈希数据的每一个字节并格式化为十六进制字符串  
    for (int i = 0; i < data.length; i++)
    {
        sbuilder.append(data[i].tostring());
    }

    // 返回十六进制字符串  
    return sbuilder.tostring();
}
/// <summary>  
/// 对象序列化成 xml string  
/// </summary>  
public static string xmlserialize<t>(t obj)
{
    string xmlstring = string.empty;
    xmlserializer xmlserializer = new xmlserializer(typeof(t));
    using (memorystream ms = new memorystream())
    {
        xmlserializer.serialize(ms, obj);
        xmlstring = encoding.utf8.getstring(ms.toarray());
    }
    return xmlstring;
}
/// <summary>
/// 从字符串里随机得到，规定个数的字符串.
/// </summary>
/// <param name="allchar"></param>
/// <param name="codecount"></param>
/// <returns></returns>
public static string getrandomstring(int codecount)
{
    string allchar = "1,2,3,4,5,6,7,8,9,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";
    string[] allchararray = allchar.split(',');
    string randomcode = "";
    int temp = -1;
    random rand = new random();
    for (int i = 0; i < codecount; i++)
    {
        if (temp != -1)
        {
            rand = new random(temp * i * ((int)datetime.now.ticks));
        }
        int t = rand.next(allchararray.length - 1);
        while (temp == t)
        {
            t = rand.next(allchararray.length - 1);
        }
        temp = t;
        randomcode += allchararray[t];
    }

    return randomcode;
}


public static string getwebclientip()
{
    string userip = "ip";

    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   
        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;
}




private static bool checkvalidationresult(object sender, x509certificate certificate, x509chain chain, sslpolicyerrors errors)
{
    return true; //总是接受   
}

public static httpwebresponse createposthttpresponse(string url, string datas, encoding charset)
{
    httpwebrequest request = null;
    //httpsq请求
    servicepointmanager.servercertificatevalidationcallback = new remotecertificatevalidationcallback(checkvalidationresult);
    request = webrequest.create(url) as httpwebrequest;
    request.protocolversion = httpversion.version10;
    request.method = "post";
    request.contenttype = "application/x-www-form-urlencoded";

    //如果需要post数据   
    //if (!(parameters == null || parameters.count == 0))
    //{
    stringbuilder buffer = new stringbuilder();
    //int i = 0;
    //foreach (string key in parameters.keys)
    //{
    //    if (i > 0)
    //    {
    //        buffer.appendformat("&{0}={1}", key, parameters[key]);
    //    }
    //    else
    //    {
    //        buffer.appendformat("{0}={1}", key, parameters[key]);
    //    }
    //    i++;
    //}
    buffer.appendformat(datas);
    byte[] data = charset.getbytes(buffer.tostring());
    using (stream stream = request.getrequeststream())
    {
        stream.write(data, 0, data.length);
    }
    //}
    return request.getresponse() as httpwebresponse;
}


public string getsignstring(dictionary<string, string> dic)
{
    string key = system.web.configuration.webconfigurationmanager.appsettings["key"].tostring();//商户平台 api安全里面设置的key  32位长度
                                                                                                //排序
    dic = dic.orderby(d => d.key).todictionary(d => d.key, d => d.value);
    //连接字段
    var sign = dic.aggregate("", (current, d) => current + (d.key + "=" + d.value + "&"));
    sign += "key=" + key;
    //md5
    // sign = system.web.security.formsauthentication.hashpasswordforstoringinconfigfile(sign, "md5").toupper();
    system.security.cryptography.md5 md5 = system.security.cryptography.md5.create();
    sign = bitconverter.tostring(md5.computehash(encoding.utf8.getbytes(sign))).replace("-", null);
    return sign;
}


/// <summary>  
/// 获取时间戳  
/// </summary>  
/// <returns></returns>  
public static string gettimestamp()
{
    timespan ts = datetime.utcnow - new datetime(1970, 1, 1, 0, 0, 0, 0);
    return convert.toint64(ts.totalseconds).tostring();
}

}

 

      微信返回信息接收后台页面notify_url.ashx

 

<%@ webhandler language="c#" class="notify_url" %>

using system;
using system.web;
using system.collections.generic;
using system.data;
using system.io;
using system.text;
using system.xml;
using system.net;
public class notify_url : ihttphandler
{
    public string return_result = "";
    public void processrequest(httpcontext context)
    {
        context.response.contenttype = "text/plain";
        context.response.write("hello world");


        string xmldata = getpoststr();//获取请求数据
        if (xmldata == "")
        {

        }
        else
        {
            var dic = new dictionary<string, string>
{
    {"return_code", "success"},
    {"return_msg","ok"}

};
            var sb = new stringbuilder();
            sb.append("<xml>");


            foreach (var d in dic)
            {
                sb.append("<" + d.key + ">" + d.value + "</" + d.key + ">");
            }
            sb.append("</xml>");





            //把数据重新返回给客户端
            dataset ds = new dataset();
            stringreader stram = new stringreader(xmldata);
            xmltextreader datareader = new xmltextreader(stram);
            ds.readxml(datareader);
            if (ds.tables[0].rows[0]["return_code"].tostring() == "success")
            {


                string wx_appid = "";//微信开放平台审核通过的应用appid
                string wx_mch_id = "";//微信支付分配的商户号

                string wx_nonce_str = "";// 	随机字符串，不长于32位
                string wx_sign = "";//签名，详见签名算法
                string wx_result_code = "";//success/fail

                string wx_return_code = "";
                string wx_openid = "";//用户在商户appid下的唯一标识
                string wx_is_subscribe = "";//用户是否关注公众账号，y-关注，n-未关注，仅在公众账号类型支付有效
                string wx_trade_type = "";// 	app
                string wx_bank_type = "";// 	银行类型，采用字符串类型的银行标识，银行类型见银行列表
                string wx_fee_type = "";// 	货币类型，符合iso4217标准的三位字母代码，默认人民币：cny，其他值列表详见货币类型


                string wx_transaction_id = "";//微信支付订单号
                string wx_out_trade_no = "";//商户系统的订单号，与请求一致。
                string wx_time_end = "";// 	支付完成时间，格式为yyyymmddhhmmss，如2009年12月25日9点10分10秒表示为20091225091010。其他详见时间规则
                int wx_total_fee = -1;// 	订单总金额，单位为分
                int wx_cash_fee = -1;//现金支付金额订单现金支付金额，详见支付金额


                #region  数据解析
                //列 是否存在
                string signstr = "";//需要前面的字符串
                                    //wx_appid
                if (ds.tables[0].columns.contains("appid"))
                {
                    wx_appid = ds.tables[0].rows[0]["appid"].tostring();
                    if (!string.isnullorempty(wx_appid))
                    {
                        signstr += "appid=" + wx_appid;
                    }
                }

                //wx_bank_type
                if (ds.tables[0].columns.contains("bank_type"))
                {
                    wx_bank_type = ds.tables[0].rows[0]["bank_type"].tostring();
                    if (!string.isnullorempty(wx_bank_type))
                    {
                        signstr += "&bank_type=" + wx_bank_type;
                    }
                }
                //wx_cash_fee
                if (ds.tables[0].columns.contains("cash_fee"))
                {
                    wx_cash_fee = convert.toint32(ds.tables[0].rows[0]["cash_fee"].tostring());

                    signstr += "&cash_fee=" + wx_cash_fee;
                }

                //wx_fee_type
                if (ds.tables[0].columns.contains("fee_type"))
                {
                    wx_fee_type = ds.tables[0].rows[0]["fee_type"].tostring();
                    if (!string.isnullorempty(wx_fee_type))
                    {
                        signstr += "&fee_type=" + wx_fee_type;
                    }
                }

                //wx_is_subscribe
                if (ds.tables[0].columns.contains("is_subscribe"))
                {
                    wx_is_subscribe = ds.tables[0].rows[0]["is_subscribe"].tostring();
                    if (!string.isnullorempty(wx_is_subscribe))
                    {
                        signstr += "&is_subscribe=" + wx_is_subscribe;
                    }
                }

                //wx_mch_id
                if (ds.tables[0].columns.contains("mch_id"))
                {
                    wx_mch_id = ds.tables[0].rows[0]["mch_id"].tostring();
                    if (!string.isnullorempty(wx_mch_id))
                    {
                        signstr += "&mch_id=" + wx_mch_id;
                    }
                }

                //wx_nonce_str
                if (ds.tables[0].columns.contains("nonce_str"))
                {
                    wx_nonce_str = ds.tables[0].rows[0]["nonce_str"].tostring();
                    if (!string.isnullorempty(wx_nonce_str))
                    {
                        signstr += "&nonce_str=" + wx_nonce_str;
                    }
                }

                //wx_openid
                if (ds.tables[0].columns.contains("openid"))
                {
                    wx_openid = ds.tables[0].rows[0]["openid"].tostring();
                    if (!string.isnullorempty(wx_openid))
                    {
                        signstr += "&openid=" + wx_openid;
                    }
                }

                //wx_out_trade_no
                if (ds.tables[0].columns.contains("out_trade_no"))
                {
                    wx_out_trade_no = ds.tables[0].rows[0]["out_trade_no"].tostring();
                    if (!string.isnullorempty(wx_out_trade_no))
                    {
                        signstr += "&out_trade_no=" + wx_out_trade_no;
                    }
                }

                //wx_result_code 
                if (ds.tables[0].columns.contains("result_code"))
                {
                    wx_result_code = ds.tables[0].rows[0]["result_code"].tostring();
                    if (!string.isnullorempty(wx_result_code))
                    {
                        signstr += "&result_code=" + wx_result_code;
                    }
                }

                //wx_result_code 
                if (ds.tables[0].columns.contains("return_code"))
                {
                    wx_return_code = ds.tables[0].rows[0]["return_code"].tostring();
                    if (!string.isnullorempty(wx_return_code))
                    {
                        signstr += "&return_code=" + wx_return_code;
                    }
                }

                //wx_sign 
                if (ds.tables[0].columns.contains("sign"))
                {
                    wx_sign = ds.tables[0].rows[0]["sign"].tostring();
                    //if (!string.isnullorempty(wx_sign))
                    //{
                    //    signstr += "&sign=" + wx_sign;
                    //}
                }

                //wx_time_end
                if (ds.tables[0].columns.contains("time_end"))
                {
                    wx_time_end = ds.tables[0].rows[0]["time_end"].tostring();
                    if (!string.isnullorempty(wx_time_end))
                    {
                        signstr += "&time_end=" + wx_time_end;
                    }
                }

                //wx_total_fee
                if (ds.tables[0].columns.contains("total_fee"))
                {
                    wx_total_fee = convert.toint32(ds.tables[0].rows[0]["total_fee"].tostring());

                    signstr += "&total_fee=" + wx_total_fee;
                }

                //wx_trade_type
                if (ds.tables[0].columns.contains("trade_type"))
                {
                    wx_trade_type = ds.tables[0].rows[0]["trade_type"].tostring();
                    if (!string.isnullorempty(wx_trade_type))
                    {
                        signstr += "&trade_type=" + wx_trade_type;
                    }
                }

                //wx_transaction_id
                if (ds.tables[0].columns.contains("transaction_id"))
                {
                    wx_transaction_id = ds.tables[0].rows[0]["transaction_id"].tostring();
                    if (!string.isnullorempty(wx_transaction_id))
                    {
                        signstr += "&transaction_id=" + wx_transaction_id;
                    }
                }

                #endregion

                //追加key 密钥
                signstr += "&key=" + system.web.configuration.webconfigurationmanager.appsettings["key"].tostring();
                //签名正确
                string orderstrwhere = "ordernumber='" + wx_out_trade_no + "'";



                if (wx_sign == system.web.security.formsauthentication.hashpasswordforstoringinconfigfile(signstr, "md5").toupper())
                {
                    //签名正确   处理订单操作逻辑


                }
                else
                {
                    //追加备注信息

                }

            }
            else
            {
                // 返回信息，如非空，为错误原因  签名失败 参数格式校验错误
                string return_msg = ds.tables[0].rows[0]["return_msg"].tostring();

            }


            return_result = sb.tostring();
        }
    }


    public bool isreusable
    {
        get
        {
            return false;
        }
    }

    //获得post过来的数据
    public string getpoststr()
    {
        int32 intlen = convert.toint32(system.web.httpcontext.current.request.inputstream.length);
        byte[] b = new byte[intlen];
        system.web.httpcontext.current.request.inputstream.read(b, 0, intlen);
        return system.text.encoding.utf8.getstring(b);
    }
}