路由缓存

<!-- keep-alive表示该标签内的组件会缓存数据，切走又切换回来时会保存之前留下的讯息，include表示只保存某个路由的数据 -->
<!--注意News为组件名！！！而非路由规则里的路由名-->
  <keep-alive include="News">
    <router-view></router-view>
  </keep-alive>

路由器router上的前进后退方法

<template>
 <div>
 <div class="col-xs-offset-2 col-xs-8">
 <div class="page-header"><h2>Vue Router Demo</h2></div>
 <button @click="toBack">后退</button
      ><button @click="toForward">前进</button
      ><button @click="toGo">go操作</button>
 </div>
 </div>
</template>

<script>
export default {
 name: "Banner",
 methods: {
 toBack() {
 this.$router.back();
    },
 toForward() {
 this.$router.forward();
    },
 toGo() {
 //go操作既可以前进也可以后退，数字为正即前进，为负即后退，下面表示前进两步
 this.$router.go(2);
    },
  },
};
</script>