window.onunload = function(){      
        var a_n = window.event.screenX - window.screenLeft;      
        var a_b = a_n > document.documentElement.scrollWidth-20;      
        if(a_b && window.event.clientY< 0 || window.event.altKey){      
                  alert('關閉頁面行為');
        }else{
                  alert('跳轉或者刷新頁面行為');    
            }
}