<template>
 <el-table
   :data="tableData5"
   style="width: 100%"
   row-key="id"
   :expand-row-keys="expands"
   @row-click="rowClick">
  <el-table-column type="expand">
   <template slot-scope="props">
    <el-form label-position="left" inline class="demo-table-expand">
     <el-form-item label="商品名称">
      <span>{{ props.row.name }}</span>
     </el-form-item>
     <el-form-item label="所属店铺">
      <span>{{ props.row.shop }}</span>
     </el-form-item>
     <el-form-item label="商品 ID">
      <span>{{ props.row.id }}</span>
     </el-form-item>
     <el-form-item label="店铺 ID">
      <span>{{ props.row.shopId }}</span>
     </el-form-item>
     <el-form-item label="商品分类">
      <span>{{ props.row.category }}</span>
     </el-form-item>
     <el-form-item label="店铺地址">
      <span>{{ props.row.address }}</span>
     </el-form-item>
     <el-form-item label="商品描述">
      <span>{{ props.row.desc }}</span>
     </el-form-item>
    </el-form>
   </template>
  </el-table-column>
  <el-table-column
    label="商品 ID"
    prop="id">
  </el-table-column>
  <el-table-column
    label="商品名称"
    prop="name">
  </el-table-column>
  <el-table-column
    label="描述"
    prop="desc">
  </el-table-column>
 </el-table>
</template>
 
<style>
 .demo-table-expand {
  font-size: 0;
 }
 .demo-table-expand label {
  width: 90px;
  color: #99a9bf;
 }
 .demo-table-expand .el-form-item {
  margin-right: 0;
  margin-bottom: 0;
  width: 50%;
 }
</style>
 
<script>
 export default {
  data() {
   return {
    tableData5: [{
     id: '12987122',
     name: '好滋好味鸡蛋仔',
     category: '江浙小吃、小吃零食',
     desc: '荷兰优质淡奶，奶香浓而不腻',
     address: '上海市普陀区真北路',
     shop: '王小虎夫妻店',
     shopId: '10333'
    }, {
     id: '12987123',
     name: '好滋好味鸡蛋仔',
     category: '江浙小吃、小吃零食',
     desc: '荷兰优质淡奶，奶香浓而不腻',
     address: '上海市普陀区真北路',
     shop: '王小虎夫妻店',
     shopId: '10333'
    }, {
     id: '12987125',
     name: '好滋好味鸡蛋仔',
     category: '江浙小吃、小吃零食',
     desc: '荷兰优质淡奶，奶香浓而不腻',
     address: '上海市普陀区真北路',
     shop: '王小虎夫妻店',
     shopId: '10333'
    }, {
     id: '12987126',
     name: '好滋好味鸡蛋仔',
     category: '江浙小吃、小吃零食',
     desc: '荷兰优质淡奶，奶香浓而不腻',
     address: '上海市普陀区真北路',
     shop: '王小虎夫妻店',
     shopId: '10333'
    }],
 
 
    // 要展开的行，数值的元素是row的key值
    expands: []
   }
  },
  methods:{
   //在<table>里，我们已经设置row的key值设置为每行数据id：row-key="id"
   rowClick(row, event, column) {
    Array.prototype.remove = function (val) {
     let index = this.indexOf(val);
     if (index > -1) {
      this.splice(index, 1);
     }
    };
 
    if (this.expands.indexOf(row.id) < 0) {
     this.expands.push(row.id);
    } else {
     this.expands.remove(row.id);
    }
 
   }
  }
 
 }
</script>

row-key="id"
:expand-row-keys="expands"
@row-click="rowClick"

if (this.expands.indexOf(row.id) < 0) {
     this.expands = []
     this.expands.push(row.id);
    } else {
     this.expands.remove(row.id);
    }