if (Request.HttpMethod.ToLower() == "get")
            {
                Validate();
            } 

        public void Validate()
        {
                 //微信接口接入验证代码
                string signature = Request["signature"];
                string token = "Your token";
                string timestamp = Request["timestamp"];
                string nonce = Request["nonce"];
                string echostr = Request["echostr"];

                string[] temp = { token, timestamp, nonce };
                Array.Sort(temp);
                string str = string.Join("", temp);
                string sha1Str = FormsAuthentication.HashPasswordForStoringInConfigFile(str, "SHA1");

                if (sha1Str.ToLower() == signature.ToLower())
                {
                    Response.Write(echostr);
                }
        }

else if (Request.HttpMethod.ToLower() == "post")
            {
                //微信服务器发送信息是通过post请求，向发送者以流的形式发送xml
                Stream xmlStream = Request.InputStream;
                XmlDocument doc = new XmlDocument();
                doc.Load(xmlStream);
                XmlElement root = doc.DocumentElement;
                string toUserName = root.SelectSingleNode("ToUserName").InnerText;
                string fromUserName = root.SelectSingleNode("FromUserName").InnerText;
                int createTime = int.Parse(root.SelectSingleNode("CreateTime").InnerText);
                string msgType = root.SelectSingleNode("MsgType").InnerText;
                string content = root.SelectSingleNode("Content").InnerText;
                long msgId = Int64.Parse(root.SelectSingleNode("MsgId").InnerText);
                
            }
　　　　　//因为服务器返回的是时间戳，即现在的时间与1970年1月1日8时0分0秒的秒数差，所以可以用此函数对时间进行处理
        public DateTime GetDateTime(int timeSpan)
        {
            return new DateTime(1970,1,1,8,0,0).AddSeconds(timeSpan);
        }

//微信服务器接收信息是通过post请求，向接收者以流的形式发送xml
                /*
                 格式为：
                    <xml>
                    <ToUserName><![CDATA[toUser]]>          </ToUserName>
                    <FromUserName><![CDATA[fromUser]]></FromUserName>
                    <CreateTime>12345678</CreateTime>
                    <MsgType><![CDATA[text]]></MsgType>
                    <Content><![CDATA[你好]]></Content>
                    </xml>
                 */
                string reXml = string.Format(@"<xml>
                    <ToUserName><![CDATA[{0}]]></ToUserName>
                    <FromUserName><![CDATA[{1}]]></FromUserName>
                    <CreateTime>{2}</CreateTime>
                    <MsgType><![CDATA[text]]></MsgType>
                    <Content><![CDATA[{3}]]></Content>
                    </xml>", fromUserName, toUserName, GetSecond(), "已接收到你的消息[服务器自动回复]");
                Response.Write(reXml);

　　　　　　 public int GetSecond()
        　　{
            　　return (int)(DateTime.Now - new DateTime(1970, 1, 1, 8, 0, 0)).TotalSeconds;
        　　}