理解：一个路由（route）就是一组映射关系（key-value）,多个路由需要路由器（router）进行管理。每个组件都有自己得$route属性，里面存储着自己的路由信息。整个应用只有一个router，可以通过组件的$router属性获取。

基本使用

1.安装vue-router，命令：npm i vue-router

2.应用插件：Vue.use(VueRouter)

3.编写router配置项:

import Vue from 'vue'
import VueRouter from 'vue-router'
import Home from '../views/Home.vue'

Vue.use(VueRouter)

const routes = [
 {
   path: '/',
   name: 'Home',
   component: Home
 },
 {
   path: '/about',
   name: 'About',
   // route level code-splitting
   // this generates a separate chunk (about.[hash].js) for this route
   // which is lazy-loaded when the route is visited.
   component: () => import(/* webpackChunkName: "about" */ '../views/About.vue'),
   
 }
]

const router = new VueRouter({
 mode: 'history',
 base: process.env.BASE_URL,
 routes
})

export default router

4.实现切换（active-class可配置高亮样式）

<router-link active-class="active" to="/about">About</router-link>

5.指定展示位置

<router-view></router-view>

多级路由

1.配置路由规则时，使用children配置项

import Vue from 'vue'
import VueRouter from 'vue-router'
import Home from '../views/Home.vue'

Vue.use(VueRouter)

const routes = [
  {
    path: '/',
    name: 'Home',
    component: Home
  },
  {
    path: '/about',
    name: 'About',
    // route level code-splitting
    // this generates a separate chunk (about.[hash].js) for this route
    // which is lazy-loaded when the route is visited.
    component: () => import(/* webpackChunkName: "about" */ '../views/About.vue'),
    children:[
      {
        path:'person',
        name:'Person',
        component: () => import('../views/Person'),
        children:[
          {
            name:'Info',
            path:'info',
            component: () => import('../views/Info')
          }
        ]
      }
    ]
  }
]

const router = new VueRouter({
  mode: 'history',
  base: process.env.BASE_URL,
  routes
})

export default router

2.跳转（要写完整路径）：

<router-link to="/about/news">News</router-link>

路由的query参数

1.传递参数

<!-- 跳转并携带query参数，to的字符串写法 -->
<router-link :to="/home/message/detail?id=666&title=你好">跳转</router-link>
				
<!-- 跳转并携带query参数，to的对象写法 -->
<router-link 
	:to="{
		path:'/home/message/detail',
		query:{
		   id:666,
            title:'你好'
		}
	}"
>跳转</router-link>

2.接收参数：

$route.query.id
$route.query.title

命名路由

1.作用：简化路由的跳转
2.使用：

1. 命名
const routes = [
  {
    path: '/',
    name: 'Home', //路由命名
    component: Home
  }
]


2.跳转

<router-link :to="{
          name:'Info', //跳转到name=Info的组件
          query:{
            name:person.name,
            age:person.age
          }
        }">
          成员{{index}}
</router-link>

路由的params参数

1.配置路由，声明接收params参数

{
    path: '/about',
    name: 'About',
    component: () => import(/* webpackChunkName: "about" */ '../views/About.vue'),
    children:[
      {
        path:'person',
        name:'Person',
        component: () => import('../views/Person'),
        children:[
          {
            name:'Info',
            path:'info/:name/:age',  //使用占位符声明接收params参数
            component: () => import('../views/Info')
          }
        ]
      }
    ]
  }

2.传递参数

<!-- 跳转并携带params参数，to的字符串写法 -->
<router-link :to="/about/info/张三/18">跳转</router-link>
<!-- 跳转并携带params参数，to的对象写法 -->
<router-link :to="{
          name:'Info', //跳转到name=Info的组件
          params:{   //params参数
            name:person.name,
            age:person.age
          }
        }">
          成员{{index}}
</router-link>

特别注意：路由携带params参数时，若使用to的对象写法，则不能使用path配置项，必须使用name配置！

3.接收参数

<div>
    <p>姓名：{{$route.params.name}}</p>
    <p>年龄：{{$route.params.age}}</p>
  </div>