<html>
<head>
<script type="text/javascript" src="/jquery/jquery.js"></script>
<script type="text/javascript">
$(document).ready(function(){
  $("button").click(function(){
    $("p").offset(function(n,c){ // 此处的n和c分别代表什么意思??
     newPos=new Object();
        newPos.left=c.left+100;
        newPos.top=c.top+100;
        return newPos;
    });
  });
});
</script>
</head>
<body>
<p>这是一个段落。</p>
<button>设置 p 元素的 offset 坐标</button>
</body>
</html>