javascript 代码：【复制】 
function offset(e){
	var t = e.offsetTop;
	var l = e.offsetLeft;
	var w = e.offsetWidth;
	var h = e.offsetHeight - 2;
	while(e = e.offsetParent){
		t += e.offsetTop;
		l += e.offsetLeft;
	}
	return {
		top : t,
		left : l,
		width : w,
		height : h
	}
}