[HttpGet]
[ActionName("Index")]
public ActionResult Get(string signature,string timestamp,string nonce,string echostr)
{
  if (CheckSignature.Check(signature, timestamp, nonce, token))
  {
    return Content(echostr);
  }
  else
  {
    return Content("err");
  }

[HttpPost]
[ActionName("Index")]
public ActionResult Get(string signature, string timestamp, string nonce)
{
   StreamReader sr = new StreamReader(Request.InputStream, Encoding.UTF8);
   XmlDocument doc = new XmlDocument();
   doc.Load(sr);
   sr.Close();
   sr.Dispose();
 
   WxMessage wxMessage = new WxMessage();
   wxMessage.ToUserName = doc.SelectSingleNode("xml").SelectSingleNode("ToUserName").InnerText;
   wxMessage.FromUserName = doc.SelectSingleNode("xml").SelectSingleNode("FromUserName").InnerText;
   wxMessage.MsgType = doc.SelectSingleNode("xml").SelectSingleNode("MsgType").InnerText;
   wxMessage.CreateTime = int.Parse(doc.SelectSingleNode("xml").SelectSingleNode("CreateTime").InnerText);
 
   if (wxMessage.MsgType == "event")
   {
     wxMessage.EventName = doc.SelectSingleNode("xml").SelectSingleNode("Event").InnerText;
     if (!string.IsNullOrEmpty(wxMessage.EventName) && wxMessage.EventName == "subscribe")
     {
       string content = "您好，欢迎访问garfieldzf8测试公众平台";
       content = SendTextMessage(wxMessage, content);
       return Content(content);
    }
  }
      return Content("");
}
 
 
private string SendTextMessage(WxMessage wxmessage,string content)
{
   string result = string.Format(Message, wxmessage.FromUserName,wxmessage.ToUserName,DateTime.Now.Ticks, content);
   return result;
}
 
 
 public string Message
 {
   get
   {
     return @"<xml>
           <ToUserName><![CDATA[{0}]]></ToUserName>
           <FromUserName><![CDATA[{1}]]></FromUserName>
           <CreateTime>{2}</CreateTime>
           <MsgType><![CDATA[text]]></MsgType>
           <Content><![CDATA[{3}]]></Content>
         </xml>";
      }
  }

public class WxMessage
 {
    public string ToUserName { get; set; }
    public string FromUserName { get; set; }
    public long CreateTime { get; set; }
 
    public string Content { get; set; }
    public string MsgType { get; set; }
    public string EventName { get; set; }
    public string EventKey { get; set; }
 }