MVC Ajax调用Action时-OnActionExecuting RedirectResult 无法跳转的处理办法

public class BaseController : Controller
    {
        protected override void OnActionExecuting(ActionExecutingContext filterContext)
        {
            if (Session["userInfo"] == null)
            {
                if (filterContext.HttpContext.Request.IsAjaxRequest())
                {
                    filterContext.Result = new HttpStatusCodeResult(499);
                    filterContext.HttpContext.Response.Write("/Desktop/Login/Index");
                    return;
                }
                else
                {
                    filterContext.Result = new RedirectResult("/Desktop/Login/Index");
                    return;
                }
            }
            base.OnActionExecuting(filterContext);
        }
    }
}

(function ($) {
//有可能导致jquery里面的done方法未定义；所以有时候可以全部注释掉；
            var _ajax = $.ajax;
            $.ajax = function (opt) {
                var fn = {
                    error: function (XMLHttpRequest, textStatus, errorThrown) { },
                }
                if (opt.error)
                    fn.error = opt.error;
                var _opt = $.extend(opt, {
                    error: function (XMLHttpRequest, textStatus, errorThrown) {
                        if (XMLHttpRequest.status == "499")
                            window.location.href = "/Desktop/Login/Index";
                        else
                            fn.error(XMLHttpRequest, textStatus, errorThrown);
                    }
                });
                _ajax(_opt);
            };
        })(jQuery);

        $.ajaxSetup({
            statusCode: {
                499: function (data) {
                    window.location.href = data.responseText;
                }
            }
        });

$.ajax({
                type: "POST",
                url: "/desktop/language/index",
                data: { language: getCookie("languageCode") },
                datatype: "json",
                success: function (returndata) {
                    //alert("second success");
                }
            });

//如果是Ajax.BeginForm,跳转到登陆页方式为如下：

@using (Ajax.BeginForm("GetSystemStatusTracking", "ReportQuery",
　　new AjaxOptions() { UpdateTargetId = "TRACKING_NEWLIST",
　　　　OnBegin = "showModal",
　　　　OnComplete = "hideModal",
　　　　OnFailure = "failureProcess"
　　}))
{

}

function failureProcess(data) {
if (data.status == 499)
window.location.href = (data.responseText == '') ? window.location.href = "/Desktop/Login/Index" : data.responseText;
}

 特别注意：当用IIS发布时，客户端访问会报错“ 自定义错误模块不能识别此错误”，但调试时和本机发布本机访问都不会报错；

 初步怀疑是服务器和客户端字体解析问题导致。代码需改为如下：

$.ajaxSetup({
　　statusCode: {
　　　　499: function (data) {
　　　　　　window.location.href = "/Desktop/Login/Index";
　　　　}
　　}
});

function failureProcess(data) {
　　if (data.status == 499) {
　　　　window.location.href = "/Desktop/Login/Index";
　　}
}