Element 动态表头

<el-table
  :data="tableData"
  style="width: 100%">
  <el-table-column v-for="(item, ii) in tableColumn" :key="'0_' + ii" :label="item.title" :prop="item.prop">
    <template v-for="(jtem, jj) in item.children">
      <el-table-column :key="ii + '_' + jj" :label="jtem.title">
        <template slot-scope="scope">
          <el-button type="text" size="small" @click="buttonClick(scope, ii, jj)">{{scope.row[jtem.prop]}}</el-button>
        </template>
      </el-table-column>
    </template>
  </el-table-column>
</el-table>

tableColumn: [
  {
    title: '日期',
    prop: 'date'
  },
  {
    title: '姓名',
    prop: 'name',
    children: [
      {
        title: '地址',
        prop: 'address'
      }
    ]
  },
  {
    title: '地址',
    children: [
      {
        title: '省',
        prop: 'province'
      },
      {
        title: '市',
        prop: 'city'
      }
    ]
  }
]

tableData: [{
  date: '2016-05-01',
  name: '王小虎1',
  province: '上海1',
  city: '普陀区1',
  address: '上海市普陀区金沙江路 1',
  zip: 200333
}, {
  date: '2016-05-02',
  name: '王小虎2',
  province: '上海2',
  city: '普陀区2',
  address: '上海市普陀区金沙江路 2',
  zip: 200333
},
{
  date: '2016-05-03',
  name: '王小虎3',
  province: '上海3',
  city: '普陀区3',
  address: '上海市普陀区金沙江路 3',
  zip: 200333
}]