net core 返回404方法

public void Configure(IApplicationBuilder app, IHostingEnvironment env)
        {
            if (env.IsDevelopment())
            {
                app.UseDeveloperExceptionPage();
            }
            else
            {
                app.UseExceptionHandler("/Home/Error");
            }
            //新增
           app.UseStatusCodePagesWithReExecute("/Error/{0}");


            app.UseStaticFiles();
            app.UseCookiePolicy();

            app.UseMvc(routes =>
            {
                routes.MapRoute(
                    name: "default",
                    template: "{controller=Home}/{action=Index}/{id?}");
            });
        }

需要新建error控制器

  public class ErrorController : Controller
    {
        [Route("Error/404")]
        public IActionResult Error404()
        {
            return View();
        }

        [Route("Error/{code:int}")]
        public IActionResult Error(int code)
        {
            return View();
        }
    }

//输入错误的URL路径, 将请求到   Error404()方法