从零开始学VUE之VueRouter(导航守卫)

导航守卫

需要先定义路由,然后通过路由对象调用

import Vue from 'vue'
// 导入路由
import Router from 'vue-router'
import HelloWorld from '@/components/HelloWorld'

// import home from '../components/Home'
// import about from '../components/About'
// import user from '../components/User'

const home = () => import('../components/Home')
const homeNews = () => import('../components/HomeNews')
const homeMessage = () => import('../components/HomeMessage')

const about = () => import('../components/About')
const user = () => import('../components/User')
const profile = () => import('../components/Profile')

// Vue加载
Vue.use(Router)

// 传入路由映射配置 导出路由实例
const router = new Router({
  // 设置模式为 history
  mode: 'history',
  linkActiveClass: 'active',
  linkExactActiveClass: 'noactive',
  routes: [// 传递参数的占位符
    {
      // 在默认的情况下 重定向到主页
      path: '',
      redirect: "/home"
    }, {

      path: '/user/:userId',
      name: 'user',
      meta:{ title: '用户' },
      component: user
    }, {
      path: '/home',
      name: 'home',
      meta:{ title: '首页' },
      component: home,
      // 嵌套路由
      children: [
        {
          path: 'news',
          meta:{ title: '首页|新闻' },
          component: homeNews
        }, {
          path: 'message',
          meta:{ title: '首页|消息' },
          component: homeMessage
        }, {
          path: '',
          redirect: 'news'
        }
      ]
    }, {
      path: '/about',
      name: 'about',
      meta:{ title: '关于' },
      component: about
    }, {
      // 传递参数
      path:'/profile',
      meta:{ title: '档案' },
      component:profile
    }
  ]
})
// 前置守卫函数
router.beforeEach((to, from, next) => {
  // 路由导航守卫
  // 在路由跳转调用之前
  // from 从哪里 to 到哪里
  // document.title = to.matched[0].meta.title;
  document.title = to.meta.title;
  // 调用next放行路由
  next();
})
// 后置钩子函数
router.afterEach((to,from) => {

})

export default router