微信公众平台开发之获得ACCESSTOKEN .Net代码解析

如何认证成为开发者？请点击第一篇文章进行查看，成为了开发者之后微信平台会给您appid和secret，在订阅号中是没有的，所以因该申请一下服务号，有了ACCESSTOKEN才能做添加菜单，上传/下载图片等功能。

private string GetToken()
 {

 // 也可以这样写:
 //return GetPage("https://api.weixin.qq.com/cgi-bin/token?grant_type=client_credential&appid=你的appid&secret=你的secret", "");
 
 string res = "";
 HttpWebRequest req = (HttpWebRequest)HttpWebRequest.Create("https://api.weixin.qq.com/cgi-bin/token?grant_type=client_credential
&appid=你的appid&secret=你的secret");
 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 = Json.JSONStringToList<ACCESSTOKEN>(content);
 res = myACCESSTOKEN[0].access_token;
 
 }


 return res;
 }
 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, 0, 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;
 return content;
 }
 catch (Exception ex)
 {
 string err = ex.Message;
 Response.Write(err);
 return string.Empty;
 }
 }