<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
<style>
.active{
text-decoration: none;
color: #00a1d6;
}
</style>
</head>
<body>
<div id="app">
<a v-bind:class="{active: isActive}" v-bind:href="url">Click
<!--<img v-bind:src="img" alt="">-->
</a>
</div>
<script src="https://cdn.bootcss.com/vue/2.4.2/vue.js"></script>
<script>
var app=new Vue({
el:"#app",
data:{
url:"http://baidu.com",
// img:"https://dummyimage.com/100x100/ffcc00/ffffff"
isActive:true
}
})
</script>
</body>
</html>
v-vind:class="{active: isActive}"
键为为标签增添的类，当isAcive为true时，为标签添加active类
v-bind:属性， 可以简写为:属性