最近公司项目加了个页面，其中要求是这样的，点击对应列表，展开和收起，其实就是显示和隐藏内容部分；说来惭愧，我花了半天时间才搞出来（自黑一下~），接下来分享给大家，先上效果图：

vue页面：

<template>
 <div class="dealRecord-wrap">
 <div class="title-contant" v-for="(item,index) in items " >

 <div class="title" @click="showHide(index)">

 <h3>2018年0{{index+6}}月</h3>

 <div class="number">800笔<i></i></div>

 </div>

 <div class="contant">

 <ul>

 <li v-for="i in item.allNumber">
 {{index+6}}
 </li>
 </ul>
 </div>
 </div>
 </div>
</template>
<script>
export default{
 data(){
 return{
 items:[
 {v:'qqq',allNumber:1},

 {v:'aaa',allNumber:2},

 {v:'qqq',allNumber:3},

 ],
 }
 },
 created(){
 document.body.style.backgroundColor = '#f6f6f6';
 },

 mounted(){

 for(var i=0;i<3;i++){ //这里取值自后台返回的长度,设置页面渲染完成后是否展开，此处不展开

 document.getElementsByClassName('contant')[i].style.height = '0px';

 }

 },

 components:{

 },

 methods:{

 showHide(index){ //点击展开收起

 let contant = document.getElementsByClassName('contant')[index]; //这里我们通过参数index来让浏览器判断你点击的是哪一个列表 

 let height = contant.getBoundingClientRect().height; //获取页面元素的当前高度

 document.getElementsByTagName('i')[index].style.transform = !!height?'rotateX(0deg)':'rotateX(180deg)';

 if (!!height) {

 contant.style.height = height + 'px';

 let f = document.body.offsetHeight; //强制相应dom重绘，使最新的样式得到应用

 contant.style.height = '0px';

 } else {

 contant.style.height = 'auto';

 height = contant.getBoundingClientRect().height;

 contant.style.height = '0';

 let f = document.body.offsetHeight;

 contant.style.height = height + 'px';

 }
 }
 },

 beforeDestroy(){
 document.body.style.backgroundColor = '#fff';
 }
}
</script>
<style type="text/scss" lang="scss" scoped>
.dealRecord-wrap{margin-bottom: 100px;

 .title-contant{overflow: hidden; /* 这个是重点 */

 .title{height: 84px;padding: 0 24px;border-bottom: 1px solid #eaeaea;/*px*/

 h3{height: 84px;font-size: 28px;color: #333;display: flex;align-items: center;float: left;;margin-left: 10px;}

 .number{height: 84px;font-size: 24px;color: #666;display: flex;align-items: center;float: right;}

 .number i{display: inline-block;width: 23px;height: 13px;background: url('../../assets/images/icon_dropup@2x.png');background-repeat: no-repeat;background-size: 23px 13px;background-position: right 6px center;padding-right: 35px;display: flex;align-items: center; float: right;transform:rotateX(0deg);}

 }

 .contant{background: #fff;transition: height 1s; /* 这个也是重点 */

 ul li{padding: 0 24px;height: 142px;display: flex;align-items: center;}

 ul li:not(:last-child){border-bottom: 1px solid #f6f6f6;/*px*/}
 }
 }
}
</style>