在.net里得到一个asp.net页面的执行时间

Global.asax.cs中:  

       protected void Application_BeginRequest(Object sender, EventArgs e)
        {

            Application["StartTime"] = System.DateTime.Now;

        }

        protected void Application_EndRequest(Object sender, EventArgs e)
        {

            System.DateTime startTime = (System.DateTime)Application["StartTime"];
            System.DateTime endTime = System.DateTime.Now;
            System.TimeSpan ts = endTime - startTime;
            Response.Write("<table   border=0'   width='100%'><tr><td   align='center'   width='100%'><font   size=1   color='red'>页面执行耗时：" + ts + "秒<font></td></tr></table>");

        }