<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<script src="//libs.baidu.com/jquery/1.10.2/jquery.min.js">
</script>
<script>
$(document).ready(function(){
$("button").click(function(){
alert($("#runoob").attr("href"));
});
});
</script>
</head>
<body>
<p><a href="http://www.w3cschool.cn" id="runoob">W3Cschool教程</a></p>
<button>显示 href 属性的值</button>
</body>
</html>