ASP.NET webapi 全局异常过滤器

public class ExceptionAPIFilter : IExceptionFilter
    {
        public bool AllowMultiple => true;

        public Task ExecuteExceptionFilterAsync(HttpActionExecutedContext actionExecutedContext, CancellationToken cancellationToken)
        {
            var ex = actionExecutedContext.Exception.InnerException ?? actionExecutedContext.Exception;
            return Task.Run(() =>
            {
                string controllerName = actionExecutedContext.ActionContext.ControllerContext.ControllerDescriptor.ControllerName;
                string actionName = actionExecutedContext.ActionContext.ActionDescriptor.ActionName;
                string param = actionExecutedContext.Request.Method.ToString();
                //记录日志
                LogFile.WriteErrorLog(DateTime.Now + string.Format(" Location：{0}/{1} Param：{2} UserIP：{3} Exception：{4}", controllerName, actionName, param, "", ex.Message));
                ResultU result = new ResultU(false, 999, ex.Message);
                string json = Newtonsoft.Json.JsonConvert.SerializeObject(result);

                HttpResponseMessage httpResponse = new HttpResponseMessage();
                HttpContent httpContent = new StringContent(json);
                httpResponse.Content = httpContent;
                actionExecutedContext.Response = httpResponse;
            });
        }
    }