Mvc 异常处理 ajax的 和 不是ajax的！

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Mvc;

namespace MvcApplication1.Controllers
{
    [AttributeUsage(AttributeTargets.Class|AttributeTargets.Method,AllowMultiple=true,Inherited=true)]
    public class HandleAjaxErrorAttribute:FilterAttribute,IExceptionFilter
    {

        public void OnException(ExceptionContext filterContext)
        {

            var errorMsg = filterContext.Exception.Message;
            if (filterContext.HttpContext.Request.IsAjaxRequest())
            {
                filterContext.Result = new JsonResult()
                {
                    Data = errorMsg,
                    JsonRequestBehavior = JsonRequestBehavior.AllowGet
                };
                filterContext.ExceptionHandled = true;
            }
            else
            {


                filterContext.HttpContext.Response.Redirect("Http://www.baidu.com");
                filterContext.ExceptionHandled = true;
            }
        }
    }
}