获取鼠标位置的javascript(zz)

var Mouse = new function(){
    this.x = 0;
    this.y = 0;
    this.capture = function(evt){
        if (document.all) {//  IE
            Mouse.x = window.event.x + document.body.scrollLeft;
            Mouse.y = window.event.y + document.body.scrollTop;
        } else if (document.layers||document.getElementById) {    //  Netscape
            Mouse.x = evt.pageX;
            Mouse.y = evt.pageY;
        }
        //alert(Mouse.x + "/" + Mouse.y); //test
    };
    if (document.layers) { //netscape
        document.captureEvents(Event.MOUSEMOVE);
    }
    document.onmousemove = this.capture;
};

var Screen = new function(){
    if (document.layers||document.getElementById) {    //  Netscape
        this.width = window.innerWidth+window.pageXOffset;
        this.height = window.innerHeight+window.pageYOffset;
    } else if (document.all) {//  IE
        this.width = document.body.clientWidth+document.body.scrollLeft;
        this.height = document.body.clientHeight+document.body.scrollTop;
    }
};