防止ajax非正常访问

http://www.cnblogs.com/yagzh2000/archive/2013/06/09/3128042.html

http://www.cnblogs.com/henw/archive/2012/01/31/2333783.html

 if ("http://" + Request.UrlReferrer.Host + ":" + Request.UrlReferrer.Port == ConfigStore.CommonSettings.App_Site_Url)
             {
                 Random randnum = new Random();
                 string telcode = randnum.Next(, ).ToString();
                 return Json(new { flag = true });
             }