element ui表格 表头的的特殊处理（换行/jsx风格表头）以及上传组件的一点小问题

<!--
 * @Description: 
 * @Version: 2.0
 * @Autor: lhl
 * @Date: 2020-01-15 11:15:40
 * @LastEditors: lhl
 * @LastEditTime: xxx
 -->
<template>
  <div>
    <el-table :data="tableData" style="width: 100%">
      <el-table-column align="center" label="Date" prop="date"></el-table-column>
      <el-table-column align="center" :label="'姓名\n(注：element ui 表格表头换行)'" prop="name"></el-table-column>
      <el-table-column align="center" :render-header="renderHeader">
        <template slot-scope="scope">
          <span>{{scope.row.address}}</span>
        </template>
      </el-table-column>
    </el-table>
  </div>
</template>

<script>
import child from "./child";
export default {
  components: {
    child
  },
  data() {
    return {
      tableData: [
        {
          date: "2016-05-02",
          name: "王小虎",
          address: "上海市普陀区金沙江路 1518 弄"
        },
        {
          date: "2016-05-04",
          name: "王小虎",
          address: "上海市普陀区金沙江路 1517 弄"
        }
      ]
    };
  },
  mounted() {

  },
  created() {
    
  },
  methods: {
    renderHeader(h) {
      return (
        <div style="display: flex;justify-content: center;align-items: center;">
          <div>地址</div>
          <el-tooltip
            class="item"
            effect="dark"
            content="tooltip的使用。"
            placement="top"
          >
            <i class="el-icon-question"></i>
          </el-tooltip>
        </div>
      );
    }
  }
};
</script>

<style lang="scss">
  .el-table .cell{
    white-space:pre-line;
  }
</style>

 使用element-ui  el-upload上传图片，上传图片后再次打开还是会有原来的图片，想要清空原来上传的图片，只需要在组件上绑定 ref，在提交成功后的方法里调用 this.$refs.upload.clearFiles(); 就可以清除原来上传的文件；