微信公众平台开发---建立服务器与微信公众平台的链接

            string echoStr = Request.QueryString["echostr"];
            string signature = Request.QueryString["signature"];
            string timestamp = Request.QueryString["timestamp"];
            string nOnce= Request.QueryString["nonce"];
                string tokenStr = "com001";//按自己需求定义或获取一个token      
                bool b = false;
                string[] arrTmp = new string[] { tokenStr, timestamp, nonce };
                Array.Sort(arrTmp);

                string restr = arrTmp[0].ToString() + arrTmp[1].ToString() + arrTmp[2].ToString();
                restr = System.Web.Security.FormsAuthentication.HashPasswordForStoringInConfigFile(restr, "SHA1").ToLower();
                if (signature == restr)
                {
                    b = true;
                }
                else
                {
                    b = false;
                }
                if (b)
                {
                    HttpContext.Current.Response.Write(echoStr);
                    HttpContext.Current.Response.End();
                }
                else
                {
                    HttpContext.Current.Response.Write("验证失败");
                    HttpContext.Current.Response.End();
                }