jquery add()方法
<html>
<meta charset="utf-8">
<head>
<script type="text/javascript" src="js/jquery.js"></script>
</script>
<script>
$(document).ready(function(element,context){
//$("h1").add("p").add("span","s").css("background-color","yellow");
});
</script>
</head>
<body>
<div class = 'div1'>
<a class='a1'>1</a>
<span class='a2'>2</span>
</div>
<p>
<a class='a2'>3</a>
</p>
<script type="text/javascript">
$('a.a2').add('.a1','.div1').css('background-color','red');
</script>
</body>
</html>
