element中table多级表头组件固定列

多级表头固定列需要给一级表头添加fixed属性，且一级列宽度=子级的宽。

下方为具体实现代码

<template>
  <el-table :data="tableData" style="width: 100%">
    <el-table-column
      type="index"
      label="序号"
      width="55"
      align="center"
      fixed
    />
    <el-table-column label="个人信息" width="780px" fixed>
      <el-table-column
        prop="name"
        label="姓名"
        width="120"
        show-overflow-tooltip
      >
      </el-table-column>
      <el-table-column prop="province" label="省份" width="120">
      </el-table-column>
      <el-table-column prop="city" label="市区" width="120"> </el-table-column>
      <el-table-column prop="address" label="地址" width="300">
      </el-table-column>
      <el-table-column prop="zip" label="邮编" width="120"> </el-table-column>
    </el-table-column>
    <el-table-column prop="date" label="日期" width="150"> </el-table-column>
    <el-table-column prop="date" label="日期" width="150"> </el-table-column>
    <el-table-column prop="date" label="日期" width="150"> </el-table-column>
    <el-table-column prop="date" label="日期" width="150"> </el-table-column>
    <el-table-column prop="date" label="日期" width="150"> </el-table-column>
    <el-table-column prop="date" label="日期" width="150"> </el-table-column>
    <el-table-column prop="date" label="日期" width="150"> </el-table-column>
    <el-table-column prop="date" label="日期" width="150"> </el-table-column>
    <el-table-column prop="date" label="日期" width="150"> </el-table-column>
    <el-table-column prop="date" label="日期" width="150"> </el-table-column>
    <el-table-column prop="date" label="日期" width="150"> </el-table-column>
    <el-table-column prop="date" label="日期" width="150"> </el-table-column>
    <el-table-column prop="date" label="日期" width="150"> </el-table-column>
    <el-table-column prop="date" label="日期" width="150"> </el-table-column>
    <el-table-column prop="date" label="日期" width="150"> </el-table-column>
    <el-table-column prop="date" label="日期" width="150"> </el-table-column>
  </el-table>
</template>

<script>
export default {
  data() {
    return {
      tableData: [
        {
          date: "2016-05-03",
          name: "王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎",
          province: "上海",
          city: "普陀区",
          address: "上海市普陀区金沙江路 1518 弄",
          zip: 200333,
        },
        {
          date: "2016-05-02",
          name: "王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎",
          province: "上海",
          city: "普陀区",
          address: "上海市普陀区金沙江路 1518 弄",
          zip: 200333,
        },
        {
          date: "2016-05-04",
          name: "王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎",
          province: "上海",
          city: "普陀区",
          address: "上海市普陀区金沙江路 1518 弄",
          zip: 200333,
        },
        {
          date: "2016-05-01",
          name: "王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎",
          province: "上海",
          city: "普陀区",
          address: "上海市普陀区金沙江路 1518 弄",
          zip: 200333,
        },
        {
          date: "2016-05-08",
          name: "王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎",
          province: "上海",
          city: "普陀区",
          address: "上海市普陀区金沙江路 1518 弄",
          zip: 200333,
        },
        {
          date: "2016-05-06",
          name: "王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎",
          province: "上海",
          city: "普陀区",
          address: "上海市普陀区金沙江路 1518 弄",
          zip: 200333,
        },
        {
          date: "2016-05-07",
          name: "王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎王小虎",
          province: "上海",
          city: "普陀区",
          address: "上海市普陀区金沙江路 1518 弄",
          zip: 200333,
        },
      ],
    };
  },
};
</script>