网页的加载时间

Global.asax

protected void Application_BeginRequest(Object sender, EventArgs e)
        {
            Application["start"] = DateTime.Now ;                    }

        protected void Application_EndRequest(Object sender, EventArgs e)
        {
            System.TimeSpan aa = DateTime.Now -(System.DateTime) Application["start"];
            
            Response.Write(aa.TotalSeconds.ToString("#00.000"));
        }