示例
修改a链接的显示文本与超链接地址
需求
希望点击按钮切换样式
<!doctype html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport"
content="width=device-width, user-scalable=no, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>Document</title>
<style>
.yy {
background-color: yellow;
}
.bb {
background-color: blue;
}
</style>
</head>
<body>
<button id="y">黄色</button>
<button id="b">蓝色</button>
<script>
var by = document.querySelector("#y")
var bb = document.querySelector("#b")
</script>
</body>
</html>
