npm install vue-router --save

 "dependencies": {
  "vue": "^2.3.3",
  "vue-router": "^2.7.0"
 },

//ES6语法导入
import VueRouter from 'vue-router'
//注册
Vue.use(VueRouter)

const router = new VueRouter({
 mode: 'history',
 routes:[
  {path: '/', component:DemoHome},
  {path: '/about', component:DemoAbout},
  {path: '/contact', component:DemoContact}
 ]
})

<template>
 <div id="home">
  <h2>this is home</h2>
 </div>
</template>

<script>
 export default({
  name:'home'
 })
</script>

<style scoped>
 #home{
  width: 100%;
  height: 500px;
  background-color: khaki;
 }
</style>

<template>
 <div id="about">
  <h2>this is about</h2>
 </div>
</template>

<script>
 export default({
  name:'about'
 })
</script>

<style scoped>
#about{
 width: 100%;
 height: 500px;
 background-color: antiquewhite;
}
</style>

<template>
 <div id="contact">
  <h2>this is contact</h2>
 </div>
</template>

<script>
 export default({
  name:'contact'
 })
</script>

<style scoped>
 #contact{
  width: 100%;
  height: 500px;
  background-color: lightskyblue;
 }
</style>

import DemoHome from './components/DemoHome'
import DemoAbout from './components/DemoAbout'
import DemoContact from './components/DemoContact'

new Vue({
 el: '#app',
 router,
 template: '<App/>',
 components: { App }
})

import Vue from 'vue'
import VueRouter from 'vue-router'
import App from './App'
import DemoHome from './components/DemoHome'
import DemoAbout from './components/DemoAbout'
import DemoContact from './components/DemoContact'

Vue.use(VueRouter)

Vue.config.productionTip = false

const router = new VueRouter({
 mode: 'history',
 routes:[
  {path: '/', component:DemoHome},
  {path: '/about', component:DemoAbout},
  {path: '/contact', component:DemoContact}
 ]
})
/* eslint-disable no-new */
new Vue({
 el: '#app',
 router,
 template: '<App/>',
 components: { App }
})

<template>
 <div id="header" class="wrap">
  <div class="header">
   <h1 class="logo">
    <router-link to="/">
     ![](../assets/logo.png)
    </router-link>
   </h1>
  </div>
  <div class="top-nav">
   <div id="navList" class="navlist-wrap">
    <div class="navlist clearfix">
     <span class="nav-btn">
      <router-link to="/">首页</router-link>
     </span>
     <span class="nav-btn">
      <router-link to="/about">关于</router-link>
     </span>
     <span class="nav-btn">
      <router-link to="/contact">联系方式</router-link>
     </span>
    </div>
   </div>
  </div>
 </div>
</template>

<script>
 export default({
  name:'header',
  data:function () {
   return {
    'nav-btn': 'nav-btn'
   }
  }
 })
</script>

<style scoped>
 .header{width:1105px;margin:0 auto;height:111px;padding:12px 0 18px;position:relative;*z-index:1}
 .header .logo{height:86px;width:256px;margin-top:25px}
 .top-nav .navlist-wrap{width:1050px;margin:0 auto;position:relative}
 .top-nav .navlist{position:absolute;right:130PX;top:-40PX}
 .top-nav .navlist .nav-btn
 {
  float:left;
  margin-left:60px;
  color:#666;
  vertical-align: middle;
  text-decoration:none;
  font-size: large;
 }
</style>

<template>
 <div id="footer">
  <span>Copyright © <a href="http://www.chairis.cn" rel="external nofollow" >Chain</a>. All rights reserved</span>
 </div>
</template>

<script>
 export default({
  name:'footer'
 })
</script>

<style scoped>
 #footer
 {
  height:50px;
  position:fixed;
  bottom:0px;
  left: 0px;
  background-color: #eeeeee;
  width: 100%;
  padding-top: 10px;
 }
</style>

    <demo-header></demo-header>
    <!-- 根据路由显示的组件 -->
    <!-- TO DO -->
    <demo-footer></demo-footer>

<template>
 <div id="app">
    <demo-header></demo-header>
    <router-view></router-view>
    <demo-footer></demo-footer>
  </div>
</template>

<script>
import DemoHeader from './components/DemoHeader'
import DemoFooter from './components/DemoFooter'

export default {
 name: 'app',
 components: {
  DemoHeader,
  DemoFooter
 }
}
</script>

<style>
#app {
 -webkit-font-smoothing: antialiased;
 -moz-osx-font-smoothing: grayscale;
 text-align: center;
 color: #2c3e50;
 background-color: aliceblue;
}
</style>

import DemoHeader from './components/DemoHeader'
import DemoFooter from './components/DemoFooter'

 components: {
  DemoHeader,
  DemoFooter
 }

<template>
 <div id="app">
    <demo-header></demo-header>
    <transition name="fade" mode="out-in">
     <keep-alive>
      <router-view></router-view>
     </keep-alive>
    </transition>
    <demo-footer></demo-footer>
  </div>
</template>

.fade-enter-active, .fade-leave-active{
 transition: all .3s;
}
.fade-enter, .fade-leave-to{
 opacity: 0;
}