用js获取一行文字在DIV里的坐标

<div style="width:600px;text-align:center;font-size:22px;"><lable id="lb">oschina.net</lable></div>
 
<script type="text/javascript">
var X = $('#lb').offset().top;
var Y = $('#lb').offset().left;
document.write("x: " + X+"<br />");
document.write("y: " + Y+"<br />");
//获取相对(父元素)位置: 
var C = $('#lb').position().top; 
var D1= $('#lb').position().left; 
document.write("c: " + C+"<br />"); 
document.write("d: " + D); 
 
</script>