MVC异常处理（异常捕获）

    <customErrors mode="On">
      <error statusCode="404" redirect="~/Error/Page404" />
    </customErrors>

    public class ErrorFilter : HandleErrorAttribute
    {
        public override void OnException(ExceptionContext filterContext)
        {
            string errorMsg;
            var exception = filterContext.Exception;
            errorMsg = exception.Message;

  
            if (filterContext.RequestContext.HttpContext.Request.IsAjaxRequest())
            {
                var accept = filterContext.RequestContext.HttpContext.Request.AcceptTypes;
                if (accept.Contains("application/json"))
                {
                    filterContext.Result = new JsonResult() { Data = new { Success = false, Msg = errorMsg } };
                }
                else
                {
                    filterContext.Result = new JavaScriptResult() { Script = "alert( ‘" + errorMsg + "‘);" };
                }
            }
            else
            {
                //普通异常
                filterContext.Result = new ViewResult() { ViewName = "/Views/Test/ErrorMsg.cshtml",ViewData = new ViewDataDictionary() { { "msg", errorMsg } } };
            }
            filterContext.ExceptionHandled = true;

        }
    }

    public class FilterConfig
    {
        public static void RegisterGlobalFilters(GlobalFilterCollection filters)
        {
            filters.Add(new ErrorFilter());
        }
    }