<!DOCTYPE html>
<head>
<meta charset="utf-8"/>
<title> </title>
<script>
function change(){
var a = document.getElementById("a");
a.href="http://www.youkuaiyun.com";
a.innerHTML = "优快云";
}
</script>
</head>
<body>
<a id="a" href="http://www.baidu.com">百度</a>
<button οnclick="change()">变</button>
</body>
</html>
点击后: