9.编程式路由导航

1. 作用：不借助<router-link> 实现路由跳转，让路由跳转更加灵活

2. 具体编码：

   //$router的两个API
   this.$router.push({
   	name:'xiangqing',
   		params:{
   			id:xxx,
   			title:xxx
   		}
   })
   
   this.$router.replace({
   	name:'xiangqing',
   		params:{
   			id:xxx,
   			title:xxx
   		}
   })
   this.$router.forward() //前进
   this.$router.back() //后退
   this.$router.go() //可前进也可后退
   

> Banner.vue Message.vue

components

Banner.vue

<template>
	<div class="col-xs-offset-2 col-xs-8">
		<div class="page-header">
			<h2>Vue Router Demo</h2>
			<button @click="back">后退</button>
			<button @click="forward">前进</button>
			<button @click="test">测试一下go</button>
		</div>
	</div>
</template>

pages

About.vue

<template>
	<h2>我是About的内容</h2>
</template>

Detail.vue

<template>
	<ul>
		<li>消息编号：{{id}}</li>
		<li>消息标题：{{title}}</li>
	</ul>
</template>

Home.vue

<template>
	<div>
		<h2>Home组件内容</h2>
		<div>
			<ul class="nav nav-tabs">
				<li>
					<router-link class="list-group-item" active-class="active" to="/home/news">News</router-link>
				</li>
				<li>
					<router-link class="list-group-item" active-class="active" to="/home/message">Message</router-link>
				</li>
			</ul>
			<router-view></router-view>
		</div>
	</div>
</template>

Message.vue

<template>
	<div>
		<ul>
			<li v-for="m in messageList" :key="m.id">
				<!-- 跳转路由并携带params参数，to的字符串写法 -->
				<!-- <router-link :to="`/home/message/detail/${m.id}/${m.title}`">{{m.title}}</router-link>&nbsp;&nbsp; -->

				<!-- 跳转路由并携带params参数，to的对象写法 -->
				<router-link :to="{
					name:'xiangqing',
					query:{
						id:m.id,
						title:m.title
					}
				}">
					{{m.title}}
				</router-link>
				<button @click="pushShow(m)">push查看</button>
				<button @click="replaceShow(m)">replace查看</button>
			</li>
		</ul>
		<hr>
		<router-view></router-view>
	</div>
</template>

News.vue

<template>
	<ul>
		<li>news001</li>
		<li>news002</li>
		<li>news003</li>
	</ul>
</template>

router

index.js

// 该文件专门用于创建整个应用的路由器
import VueRouter from 'vue-router'
//引入组件
import About from '../pages/About'
import Home from '../pages/Home'
import News from '../pages/News'
import Message from '../pages/Message'
import Detail from '../pages/Detail'

//创建并暴露一个路由器
export default new VueRouter({
	routes:[
		{
			name:'guanyu',
			path:'/about',
			component:About
		},
		{
			path:'/home',
			component:Home,
			children:[
				{
					path:'news',
					component:News,
				},
				{
					path:'message',
					component:Message,
					children:[
						{
							name:'xiangqing',
							path:'detail',
							component:Detail,

							//props的第一种写法，值为对象，该对象中的所有key-value都会以props的形式传给Detail组件。
							// props:{a:1,b:'hello'}

							//props的第二种写法，值为布尔值，若布尔值为真，就会把该路由组件收到的所有params参数，以props的形式传给Detail组件。
							// props:true

							//props的第三种写法，值为函数
							props($route){
								return {
									id:$route.query.id,
									title:$route.query.title,
									a:1,
									b:'hello'
								}
							}

						}
					]
				}
			]
		}
	]
})

App.vue

<template>
  <div>
    <div class="row">
      <banner>
    </banner></div>
    <div class="row">
      <div class="col-xs-2 col-xs-offset-2">
        <div class="list-group">
					<!-- 原始html中我们使用a标签实现页面的跳转 -->
          <!-- <a class="list-group-item active" href="./about.html">About</a> -->
          <!-- <a class="list-group-item" href="./home.html">Home</a> -->

					<!-- Vue中借助router-link标签实现路由的切换 -->
					<router-link class="list-group-item" active-class="active" to="/about">About</router-link>
          <router-link class="list-group-item" active-class="active" to="/home">Home</router-link>
        </div>
      </div>
      <div class="col-xs-6">
        <div class="panel">
          <div class="panel-body">
						<!-- 指定组件的呈现位置 -->
            <router-view></router-view>
          </div>
        </div>
      </div>
    </div>
  </div>
</template>

main.js

//引入Vue
import Vue from 'vue'
//引入App
import App from './App.vue'
//引入VueRouter
import VueRouter from 'vue-router'
//引入路由器
import router from './router'

//关闭Vue的生产提示
Vue.config.productionTip = false
//应用插件
Vue.use(VueRouter)

//创建vm
new Vue({
	el:'#app',
	render: h => h(App),
	router:router
})