js如何区分页面是关闭还是刷新


            if(event.clientX>document.body.clientWidth && event.clientY<0 ||event.altKey)
            {
            
                ClosePage()
            }
            else if(event.clientY > document.body.clientHeight || event.altKey)
            {
                ClosePage()
            }
            else
            {
                alert("刷新");
            }