关闭ie窗口清除Session的解决方法

//function window.onunload() { alert(这就是你要做的事,关闭网页之后做的！ ); location = SessionClear.aspx; }
        //function window.onbeforeunload() { alert(这就是你要做的事,关闭网页之前做的！ ) }

        function window.onunload() {

            if ((window.screenLeft >= 10000 && window.screenTop >= 10000) || event.altKey) {
                alert(window.screenLeft+","+window.screenTop);
                //用户非正常关闭时需要触发的动作
                location = Handler1.ashx;
            }
        }

    </script>

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Services;
using System.Web.SessionState;

namespace WebApplication1
{
    /// <summary>
    /// $codebehindclassname$ 的摘要说明
    /// </summary>
    [WebService(Namespace = "http://tempuri.org/")]
    [WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)]
    public class Handler1 : IHttpHandler,IRequiresSessionState
    {

        public void ProcessRequest(HttpContext context)
        {
            context.Response.ContentType = "text/plain";
            context.Session.Abandon();
            context.Session.Clear();
        }

        public bool IsReusable
        {
            get
            {
                return false;
            }
        }
    }
}

<script language="javascript">
<!--
function window.onunload(){
if((window.screenLeft>=10000 && window.screenTop>=10000)||event.altKey)
{
//用户非正常关闭时需要触发的动作
}
}
-->
</script>

<script language="javascript">
function window.onUnload()
{
var newWindow;
if((window.screenLeft>=10000 && window.screenTop>=10000)||event.altKey)
{
newWindow=window.open(‘退出程序地址,网页名称,
width=0,height=0,top=4000,left=4000);//新窗口将在视区之外打开
newWindow.opener=null;
sleep(5000);
newWindow.close();//新窗口关闭
}
}
function sleep(milisecond)
{
var currentDate,beginDate=new Date();
var beginHour,beginMinute,beginSecond,beginMs;
var hourGaps,minuteGaps,secondGaps,msGaps,gaps;
beginHour=beginDate.getHours();
beginMinute=beginDate.getMinutes();
beginSecond=beginDate.getSeconds();
beginMs=beginDate.getMilliseconds();

do
{
currentDate=new Date();
hourGaps=currentDate.getHours() - beginHour;
minuteGaps=currentDate.getMinutes() - beginMinute;
secondGaps=currentDate.getSeconds() - beginSecond;
msGaps=currentDate.getMilliseconds() - beginMs;
if(hourGaps<0) hourGaps+=24; //考虑进时进分进秒的特殊情况
gaps=hourGaps*3600+ minuteGaps*60+ secondGaps;
gaps=gaps*1000+msGaps;
}while(gaps<milisecond);
}
</script>