//第一、相对于屏幕

function getMousePos(event) {

    var e = event || window.event;

    return {'x':e.screenX,'y':screenY}

}    

//第二、相对于浏览器

function getMousePos(event) {

    var e = event || window.event;

    return {'x':e.clientX,'y':clientY}

}

//第三、相对于文档

function getMousePos(event) {

    var e = event || window.event;

    var scrollX = document.documentElement.scrollLeft || document.body.scrollLeft;

    var scrollY = document.documentElement.scrollTop || document.body.scrollTop;

    var x = e.pageX || e.clientX + scrollX;

    var y = e.pageY || e.clientY + scrollY;

    //alert('x: ' + x + '\ny: ' + y);

    return { 'x': x, 'y': y };

}