基于vue展开收起动画的示例代码

<!--css-->.box{  height:200px;width: 200px;  background-color:black;}.draw-enter-active, .draw-leave-active {  transition: all 1s ease;}.draw-enter, .draw-leave-to /* .fade-leave-active below version 2.1.8 */ {  height: 0;}<div id="app">  <button @click="boxshow = !boxshow">点击展开/关闭</button>  <transition name="draw">  <!--这里的name 和 css 类名第一个字段要一样-->    <div class="box" v-show="boxshow"></div>  </transition></div></body><script src="https://cdn.jsdelivr.net/npm/vue@2.5.16/dist/vue.js"></script><script>  new Vue({    el:'#app',    data:{      boxshow:false    },  });</script>