上次遇到微信支付，发货接口的时候，官方的demo也没有提供相应的代码 ,因本人技术有限，百度 google 很久都没有asp.net 版本的，最后只好硬着头皮自己搞，没想到官方文档也是错的。

  我这一步是在支付完成之后做的回调

首先是获取access_token

http 请求方式: GET

地址：

https://api.weixin.qq.com/cgi-bin/token?grant_type=client_credential&appid=APPID&secret

=APPSECRET

 这里我分享一个获取的方法

  //AccessToken

    public string GetToken()

    {

        if (AccessToken != "")

            return AccessToken;

        string res = "";

        HttpWebRequest req = (HttpWebRequest)HttpWebRequest.Create("https://api.weixin.qq.com/cgi-bin/token?grant_type=client_credential&appid=" + System.Configuration.ConfigurationManager.AppSettings["appid"].ToString() + "&secret=" + System.Configuration.ConfigurationManager.AppSettings["secret"].ToString());

        req.Method = "GET";

        using (WebResponse wr = req.GetResponse())

        {

            HttpWebResponse myResponse = (HttpWebResponse)req.GetResponse();

            StreamReader reader = new StreamReader(myResponse.GetResponseStream(), Encoding.UTF8);

            string content = reader.ReadToEnd();

            // List<ACCESSTOKEN> myACCESSTOKEN = FluorineFx.Json.JSONStringToList<ACCESSTOKEN>(content);

            JavaScriptSerializer jser = new JavaScriptSerializer();

            ACCESSTOKEN myACCESSTOKEN = jser.Deserialize<ACCESSTOKEN>(content); //反序列化

            res = myACCESSTOKEN.access_token;

        }

        AccessToken = res;

        return res;

    }

  [Serializable]

    public class ACCESSTOKEN

    {

        public string access_token;

        public string expires_in;

    }

有了accesstoken 就可以post PostData数据到微信服务器了，

这里我先将postData数据排列到json里面，坑坑的，微信官方文档json参数的顺序是错的，需要按照a-z的顺序，这里我就没有sort数据直接排序了。

   String Timestamp = TenpayUtil.getTimestamp();

        string str = "appid=" + System.Configuration.ConfigurationManager.AppSettings["appid"].ToString() + "&appkey=" + System.Configuration.ConfigurationManager.AppSettings["Appkey"].ToString() + "&deliver_msg=ok&deliver_status=1&deliver_timestamp=" + Timestamp + "&openid=openid&out_trade_no=out_trade_no&transid=transid";

        Response.Write(str);

        AppSignature = getSha1(str).ToLower();

        Response.Write("AppSignature:"+AppSignature);

        WriteLog("AppSignature:" + AppSignature);

        string postData = "{\"appid\": \"" + System.Configuration.ConfigurationManager.AppSettings["appid"].ToString() + "\",\"openid\": \"openid\",\"transid\": \"transid\",\"out_trade_no\": \"out_trade_no\",\"deliver_timestamp\": \"" + Timestamp + "\", \"deliver_status\": \"1\",\"deliver_msg\": \"ok\",\"app_signature\":\"" + AppSignature + "\",\"sign_method\":\"sha1\"}";

        WriteLog("PostDate:" + postData);

//sha1加密是用微信官方的 

 public static String getSha1(String str)

    {

        //建立SHA1对象

        SHA1 sha = new SHA1CryptoServiceProvider();

        //将mystr转换成byte[]

        ASCIIEncoding enc = new ASCIIEncoding();

        byte[] dataToHash = enc.GetBytes(str);

        //Hash运算

        byte[] dataHashed = sha.ComputeHash(dataToHash);

        //将运算结果转换成string

        string hash = BitConverter.ToString(dataHashed).Replace("-", "");

        return hash;

    }

这里最后用了一个GetPage 后台Post数据包GetPost 给微信服务器就可以了

   public string GetPage(string posturl, string postData)

    {

        Stream outstream = null;

        Stream instream = null;

        StreamReader sr = null;

        HttpWebResponse response = null;

        HttpWebRequest request = null;

        Encoding encoding = Encoding.UTF8;

        byte[] data = encoding.GetBytes(postData);

        // 准备请求...

        try

        {

            // 设置参数

            request = WebRequest.Create(posturl) as HttpWebRequest;

            CookieContainer cookieContainer = new CookieContainer();

            request.CookieContainer = cookieContainer;

            request.AllowAutoRedirect = true;

            request.Method = "POST";

            request.ContentType = "application/x-www-form-urlencoded";

            request.ContentLength = data.Length;

            outstream = request.GetRequestStream();

            outstream.Write(data, , data.Length);

            outstream.Close();

            //发送请求并获取相应回应数据

            response = request.GetResponse() as HttpWebResponse;

            //直到request.GetResponse()程序才开始向目标网页发送Post请求

            instream = response.GetResponseStream();

            sr = new StreamReader(instream, encoding);

            //返回结果网页（html）代码

            string content = sr.ReadToEnd();

            string err = string.Empty;

            WriteLog("content:" + content);

            return content;

        }

        catch (Exception ex)

        {

            string err = ex.Message;

          Response.Write(err);

          WriteLog("err:" + err);

            return string.Empty;

        }

    }

最后直接在你的backurl(回调页面发送请求就可以了)

  /// <summary>

    /// 回调发货通知

    /// </summary>

    public void  RollBack()

    {

        String Timestamp = TenpayUtil.getTimestamp();

        string str = "appid=" + System.Configuration.ConfigurationManager.AppSettings["appid"].ToString() + "&appkey=" + System.Configuration.ConfigurationManager.AppSettings["Appkey"].ToString() + "&deliver_msg=ok&deliver_status=1&deliver_timestamp=" + Timestamp + "&openid=oF2a_t8-&out_trade_no=out_trade_no&transid=transid";

        Response.Write(str);

        AppSignature = getSha1(str).ToLower();

        Response.Write("AppSignature:"+AppSignature);

        WriteLog("AppSignature:" + AppSignature);

        string postData = "{\"appid\": \"" + System.Configuration.ConfigurationManager.AppSettings["appid"].ToString() + "\",\"openid\": \"oF2a_t8-\",\"transid\": \"transid\",\"out_trade_no\": \"out_trade_no\",\"deliver_timestamp\": \"" + Timestamp + "\", \"deliver_status\": \"1\",\"deliver_msg\": \"ok\",\"app_signature\":\"" + AppSignature + "\",\"sign_method\":\"sha1\"}";

        WriteLog("PostDate:" + postData);

        string access_token = GetToken();

        Response.Write("access_token" + access_token);

        string i = GetPage("https://api.weixin.qq.com/pay/delivernotify?access_token=" + access_token, postData);

        Response.Write("postdate"+postData);

    }

有需要的也可以留言交流.