代码:
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<head><meta charset="UTF-8"><meta name="viewport" content="width=device-width, initial-scale=1.0"><title>Document</title><style>* {margin: 0;padding: 0;}ul {display: flex;border-bottom: 2px solid #e01222;padding: 0 10px;}li {width: 100px;height: 50px;line-height: 50px;list-style: none;text-align: center;}li a {display: block;text-decoration: none;font-weight: bold;color: #333333;}li a.active {background-color: #e01222;color: #fff;}</style>
</head>
<body><!-- 创建vue实例四步1:容器 div2:引包 (开发版本包/生产版本包)3:实例 4:配置-》渲染--><div id="app"><ul><li v-for="(item,index) in list" :key="item.id " @click="activeIndex=index" ><a :class="{active:index===activeIndex}" href="#">{{item.name}}</a></li></ul></div><!-- 引入开发版本Vuejs核心包,在全局环境下就有了vue构造函数 --><script src="https://cdn.jsdelivr.net/npm/vue@2/dist/vue.js"></script> <!--2:引包 开发版本包 --><script>const app = new Vue({el:'#app',data:{activeIndex:0,// data存放响应式数据list:[{id:1,name:'京东秒杀'},{id:2,name:'每日特价'},{id:3,name:'品类秒杀'}]}})</script></body>
</html>