GPT答：

7i24.cn

<template>
  <div class="header">
    <el-menu :default-active="activeIndex" mode="horizontal" background-color="#545c64" text-color="#fff"
      active-text-color="#ffd04b">
      <el-menu-item index="/">
        <i class="el-icon-house"></i>首页
      </el-menu-item>
      <el-submenu index="user">
        <template #title>
          {{ username }}<i class="el-icon-arrow-down el-icon--right"></i>
        </template>
        <el-menu-item index="/profile">个人资料</el-menu-item>
        <el-menu-item index="/logout">退出登录</el-menu-item>
      </el-submenu>

    </el-menu>

  </div>

</template>

<script lang='ts'>
import { defineComponent } from 'vue';

export default defineComponent({
  name: 'Test',
  data() {
    return {
      activeIndex: '/',
      username: '用户名',
    };
  },
});
</script>

<style scoped lang='scss'>
.header {
  height: 60px;
}
.el-submenu__title {
  display: flex;
}
.el-submenu__title i {
  margin-left: auto;
}
</style>