微信公眾平台向特定用戶推送消息

一、首先需要將微信的openid與系統用戶綁定。

在用戶關注公眾平台的時候，回復一個鏈接，要求用戶綁定，可以設計如下消息進行回復，（openid最好進行加密處理，后者還需要用這個字段綁定fakeid）。

歡迎關注有問必答平台,< a  href='http://myweixin123.duapp.com/bind.html?openid=@openid'>點擊此處進行用戶綁定</ a >!

在bind.html頁面將openid與系統的usercode進行綁定，這個綁定過程非常簡單，這里不詳敘述。

二、將openid與fakeid進行綁定

微信公眾平台是一回一答的模式；但是在微信公眾平台后台，可以向特定用戶進行消息發送。我們利用這個機制使用代碼去模擬這個過程來實現消息推送。

首先需要模擬登錄：

using  System;

using  System.Collections.Generic;

using  System.Linq;

using  System.Web;

using  System.Security.Cryptography;

using  System.Text;

using  System.Net;

using  System.IO;

using  System.Security.Authentication;

using  System.Security.Cryptography.X509Certificates;

/// <summary>

///WeiXinLogin 的摘要說明

/// </summary>

public  class  WeiXinLogin

{

    

     /// <summary>

     /// MD5　32位加密

     /// </summary>

     /// <param name="str"></param>

     /// <returns></returns>

     static  string  GetMd5Str32( string  str)

     {

         MD5CryptoServiceProvider md5Hasher = new  MD5CryptoServiceProvider();

         // Convert the input string to a byte array and compute the hash. 

         char [] temp = str.ToCharArray();

         byte [] buf = new  byte [temp.Length];

         for  ( int  i = 0; i < temp.Length; i++)

         {

             buf[i] = ( byte )temp[i];

         }

         byte [] data = md5Hasher.ComputeHash(buf);

         // Create a new Stringbuilder to collect the bytes 

         // and create a string. 

         StringBuilder sBuilder = new  StringBuilder();

         // Loop through each byte of the hashed data  

         // and format each one as a hexadecimal string. 

         for  ( int  i = 0; i < data.Length; i++)

         {

             sBuilder.Append(data[i].ToString( "x2" ));

         }

         // Return the hexadecimal string. 

         return  sBuilder.ToString();

     }

 

     public  static  bool  ExecLogin( string  name, string  pass)

     {

         bool  result = false ;

         string  password = GetMd5Str32(pass).ToUpper();

         string  padata = "username="  + name + "&pwd="  + password + "&imgcode=&f=json" ;

         string  url = "https://mp.weixin.qq.com/cgi-bin/login?lang=zh_CN " ;//請求登錄的URL

         try

         {

             CookieContainer cc = new  CookieContainer(); //接收緩存

             byte [] byteArray = Encoding.UTF8.GetBytes(padata); // 轉化

             HttpWebRequest webRequest2 = (HttpWebRequest)WebRequest.Create(url);  //新建一個WebRequest對象用來請求或者響應url

             ServicePointManager.CertificatePolicy = new  AcceptAllCertificatePolicy();

 

             webRequest2.CookieContainer = cc;                                      //保存cookie 

             webRequest2.Method = "POST" ;                                          //請求方式是POST

             webRequest2.UserAgent = "Mozilla/5.0 (Windows NT 6.1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/30.0.1599.69 Safari/537.36" ;

             webRequest2.Referer = "https://mp.weixin.qq.com/" ;

             webRequest2.ContentType = "application/x-www-form-urlencoded" ;       //請求的內容格式為application/x-www-form-urlencoded

             webRequest2.ContentLength = byteArray.Length;

             Stream newStream = webRequest2.GetRequestStream();           //返回用於將數據寫入 Internet 資源的 Stream。

             // Send the data.

             newStream.Write(byteArray, 0, byteArray.Length);    //寫入參數

             newStream.Close();

             HttpWebResponse response2 = (HttpWebResponse)webRequest2.GetResponse();

             StreamReader sr2 = new  StreamReader(response2.GetResponseStream(), Encoding.Default);

             string  text2 = sr2.ReadToEnd();

 

             //此處用到了newtonsoft來序列化

             WeiXinRetInfo retinfo = Newtonsoft.Json.JsonConvert.DeserializeObject<WeiXinRetInfo>(text2);

             string  token = string .Empty;

             if  (retinfo.ErrMsg.Length > 0)

             {

                 token = retinfo.ErrMsg.Split( new  char [] { '&'  })[2].Split( new  char [] { '='  })[1].ToString(); //取得令牌

                 LoginInfo.LoginCookie = cc;

                 LoginInfo.CreateDate = DateTime.Now;

                 LoginInfo.Token = token;

                 result = true ;

             }

         }

         catch  (Exception ex)

         {

           

             throw  new  Exception(ex.StackTrace);

         }

         return  result;

     }

 

     public  static  class  LoginInfo

     {

         /// <summary>

         /// 登錄后得到的令牌

         /// </summary>       

         public  static  string  Token { get ; set ; }

         /// <summary>

         /// 登錄后得到的cookie

         /// </summary>

         public  static  CookieContainer LoginCookie { get ; set ; }

         /// <summary>

         /// 創建時間

         /// </summary>

         public  static  DateTime CreateDate { get ; set ; }

 

     }

     internal  class  AcceptAllCertificatePolicy : ICertificatePolicy

     {

         public  AcceptAllCertificatePolicy()

         {

         }

 

         public  bool  CheckValidationResult(ServicePoint sPoint,

            X509Certificate cert, WebRequest wRequest, int  certProb)

         {

             // Always accept 

             return  true ;

         }

     } 

}

獲取fakeid

public  static  ArrayList SubscribeMP()

{

 

     try

     {

         CookieContainer cookie = null ;

         string  token = null ;

 

 

         cookie = WeiXinLogin.LoginInfo.LoginCookie; //取得cookie

         token = WeiXinLogin.LoginInfo.Token; //取得token

 

         /*獲取用戶信息的url，這里有幾個參數給大家講一下，1.token此參數為上面的token 2.pagesize此參數為每一頁顯示的記錄條數

 

         3.pageid為當前的頁數，4.groupid為微信公眾平台的用戶分組的組id，當然這也是我的猜想不一定正確*/

         string  Url = "https://mp.weixin.qq.com/cgi-bin/contactmanage?t=user/index&pagesize=10&pageidx=0&type=0&groupid=0&token="  + token + "&lang=zh_CN" ;

         HttpWebRequest webRequest2 = (HttpWebRequest)WebRequest.Create(Url);

         webRequest2.CookieContainer = cookie;

         webRequest2.ContentType = "text/html; charset=UTF-8" ;

         webRequest2.Method = "GET" ;

         webRequest2.UserAgent = "Mozilla/5.0 (Windows NT 5.1; rv:2.0.1) Gecko/20100101 Firefox/4.0.1" ;

         webRequest2.ContentType = "application/x-www-form-urlencoded" ;

         HttpWebResponse response2 = (HttpWebResponse)webRequest2.GetResponse();

         StreamReader sr2 = new  StreamReader(response2.GetResponseStream(), Encoding.Default);

         string  text2 = sr2.ReadToEnd();

 

 

         MatchCollection mc;

 

         //由於此方法獲取過來的信息是一個html網頁所以此處使用了正則表達式，注意：（此正則表達式只是獲取了fakeid的信息如果想獲得一些其他的信息修改此處的正則表達式就可以了。）

         Regex r = new  Regex( "\"id\"\\:\\d+,\"nick_name\"" ); //定義一個Regex對象實例

         mc = r.Matches(text2);

         Int32 friendSum = mc.Count;          //好友總數

 

         string  fackID = "" ;

 

         ArrayList fackID1 = new  ArrayList();

 

         for  ( int  i = 0; i < friendSum; i++)

         {

             //"id":208989515,"nick_name"

             fackID = mc[i].Value.Replace( ",\"nick_name\"" , "" ).Split( new  char [] { ':'  })[1];

             fackID = fackID.Replace( "\"" , "" ).Trim();

             fackID1.Add(fackID);

         }

 

         return  fackID1;

 

 

 

     }

     catch  (Exception ex)

     {

         throw  new  Exception(ex.StackTrace);

     }

}

根據fakeid獲取openid

    public static string GetOpenidByFakeid(string fakeid)
    {
        try
        {
            CookieContainer cookie = null;
            string token = null;


            cookie = WeiXinLogin.LoginInfo.LoginCookie;//取得cookie
            token = WeiXinLogin.LoginInfo.Token;//取得token
            string Url = "https://mp.weixin.qq.com/cgi-bin/singlemsgpage?msgid=&source=&count=20&t=wxm-singlechat&fromfakeid=" + fakeid + "&token=" + token + "&lang=zh_CN";
            HttpWebRequest webRequest2 = (HttpWebRequest)WebRequest.Create(Url);
            webRequest2.CookieContainer = cookie;
            webRequest2.ContentType = "text/html; charset=UTF-8";
            webRequest2.Method = "GET";
            webRequest2.UserAgent = "Mozilla/5.0 (Windows NT 5.1; rv:2.0.1) Gecko/20100101 Firefox/4.0.1";
            webRequest2.ContentType = "application/x-www-form-urlencoded";
            HttpWebResponse response2 = (HttpWebResponse)webRequest2.GetResponse();
            StreamReader sr2 = new StreamReader(response2.GetResponseStream(), Encoding.UTF8);
            string text2 = sr2.ReadToEnd();
            HtmlDocument doc = new HtmlDocument();
            doc.LoadHtml(text2);
            var str = doc.GetElementbyId("json-msgList").InnerHtml;
            JArray messages = JArray.Parse(str);
            foreach (var message in messages)
            {
                string strContent = HttpUtility.HtmlDecode(message["content"].ToString());
                Regex reg = new Regex(@"(?is)<a[^>]*?href=(['""\s]?)(?<href>[^'""\s]*)\1[^>]*?>");
                MatchCollection match = reg.Matches(strContent);
                var href = "";
                foreach (Match m in match)
                {
                    href = m.Groups["href"].Value;
                }

                var openid = GetUrlParamValue(href, "openid");
                if (!string.IsNullOrEmpty(openid))
                 return openid;

            }
            return "";
        }
        catch (Exception ex)
        {
            return "";
        }
  
    }

 

由於之前有建立openid與usercode的關系，所以可以根據usercode找到openid，又可以根據openid找到fakeid。使用下面代碼進行推送：

public  static  bool  SendMessage( string  Message, string  fakeid)

{

     bool  result = false ;

     CookieContainer cookie = null ;

     string  token = null ;

     cookie = WeiXinLogin.LoginInfo.LoginCookie; //取得cookie

     token =  WeiXinLogin.LoginInfo.Token; //取得token

 

     string  strMsg = System.Web.HttpUtility.UrlEncode(Message);  //對傳遞過來的信息進行url編碼

     string  padate = "type=1&content="  + strMsg + "&error=false&tofakeid="  + fakeid + "&token="  + token + "&ajax=1" ;

     string  url = "https://mp.weixin.qq.com/cgi-bin/singlesend?t=ajax-response&lang=zh_CN" ;

 

     byte [] byteArray = Encoding.UTF8.GetBytes(padate); // 轉化

 

     HttpWebRequest webRequest2 = (HttpWebRequest)WebRequest.Create(url);

 

     webRequest2.CookieContainer = cookie; //登錄時得到的緩存

 

     webRequest2.Referer = "https://mp.weixin.qq.com/cgi-bin/singlemsgpage?token="  + token + "&fromfakeid="  + fakeid + "&msgid=&source=&count=20&t=wxm-singlechat&lang=zh_CN" ;

 

     webRequest2.Method = "POST" ;

 

     webRequest2.UserAgent = "Mozilla/5.0 (Windows NT 5.1; rv:2.0.1) Gecko/20100101 Firefox/4.0.1" ;

 

     webRequest2.ContentType = "application/x-www-form-urlencoded" ;

 

     webRequest2.ContentLength = byteArray.Length;

 

     Stream newStream = webRequest2.GetRequestStream();

 

     // Send the data.           

     newStream.Write(byteArray, 0, byteArray.Length);    //寫入參數   

 

     newStream.Close();

 

     HttpWebResponse response2 = (HttpWebResponse)webRequest2.GetResponse();

 

     StreamReader sr2 = new  StreamReader(response2.GetResponseStream(), Encoding.Default);

 

     string  text2 = sr2.ReadToEnd();

     if  (text2.Contains( "ok" ))

     {

         result = true ;

     }

     return  result;

}

　　

可以寫一個長期運行的windows服務用於建立fakeid和openid的關系，這里不再詳訴。