获取鼠标实时位置坐标

<span style="font-size:18px;"><script type="text/javascript">
//获取鼠标实时坐标
function mousePosition(ev){ 
    ev = ev || window.event; 
    if(ev.pageX || ev.pageY){ 
        return {x:ev.pageX, y:ev.pageY}; 
    } 
    return { 
        x:ev.clientX + document.body.scrollLeft - document.body.clientLeft, 
        y:ev.clientY + document.body.scrollTop - document.body.clientTop 
    }; 
}
</script></span><span style="font-size:18px;"><script type="tex