/// <summary>
        ///    HandleUnauthorizedRequest
        /// </summary>
        /// <param name="filterContext"></param>
        protected override void HandleUnauthorizedRequest(AuthorizationContext filterContext)
        {
            string result = SecurityRequestHandler.UnauthenticationRequestUrl(filterContext.RequestContext);

            if (filterContext.HttpContext.Request.IsAjaxRequest())
            {
                filterContext.HttpContext.Response.StatusCode = 401;
            }
            else
            {
                filterContext.HttpContext.Response.Redirect(result);
            }
            filterContext.HttpContext.Response.End();
        }
        ///// <summary>
        /////    HandleUnauthorizedRequest
        ///// </summary>
        ///// <param name="filterContext"></param>
        //protected override void HandleUnauthorizedRequest(AuthorizationContext filterContext)
        //{
        //    string result = SecurityRequestHandler.UnauthenticationRequestUrl(filterContext.RequestContext);

        //    if (filterContext.HttpContext.Request.IsAjaxRequest())
        //    {
        //        filterContext.HttpContext.Response.StatusCode = 401;
        //    }
        //    else
        //    {
        //        filterContext.HttpContext.Response.Redirect(result);
        //    }
        //    filterContext.HttpContext.Response.End();
        //}


        protected override bool AuthorizeCore(HttpContextBase httpContext)
        {
            bool result = base.AuthorizeCore(httpContext);

            if (result) //校验此Ticket 是否在系统中存在
            {
                result = SecurityRequestHandler.IsLogon(httpContext.Request.RequestContext);
            }
            if (!httpContext.Response.Headers.AllKeys.Contains("LogonFlag"))
            {
                httpContext.Response.AddHeader("LogonFlag", result.ToString().ToLower());
            }
            return(result);
        }