原文来自：vue 修改ant中table表格的展开图标 树形表格expandIcon自定义图标

<template #expandIcon="props"><span v-if="props.record.children?.length > 0"><divv-if="props.expanded"style="display: inline-block; margin-right: 10px"@click="(e) => {props.onExpand(props.record, e);}"><DownOutlined /></div><divv-elsestyle="display: inline-block; margin-right: 10px"@click="(e) => {props.onExpand(props.record, e);}"><RightOutlined /></div></span><span v-else style="margin-right:29px"></span></template>