用vue3写一个二级路由

Sure, here's an example of how to create a nested route in Vue 3 using the `vue-router` package:

import { createRouter, createWebHistory } from 'vue-router'
import Home from './views/Home.vue'
import About from './views/About.vue'
import Contact from './views/Contact.vue'
import Profile from './views/Profile.vue'

const routes = [
  {
    path: '/',
    name: 'Home',
    component: Home
  },
  {
    path: '/about',
    name: 'About',
    component: About
  },
  {
    path: '/contact',
    name: 'Contact',
    component: Contact
  },
  {
    path: '/profile',
    name: 'Profile',
    component: Profile,
    children: [
      {
        path: 'settings',
        name: 'Settings',
        component: Settings
      },
      {
        path: 'notifications',
        name: 'Notifications',
        component: Notifications
      }
    ]
  }
]

const router = createRouter({
  history: createWebHistory(),
  routes
})

export default router

In this example, we have a top-level route for the home page, as well as routes for the about and contact pages. We also have a nested route for the profile page, which has child routes for the settings and notifications pages.