An example of how Vue implements four-level navigation and verification code

<template>
  <div id="home-wrapper">
    <h1>{{ name }}</h1>
    <nav>
      <!-- The exit of the secondary router is in the interface of the primary router-->
      <router-link to="/one">one</router-link>
      <router-link :to="{ name: 'Two' }">two</router-link>
      <router-link :to="threeObj">three</router-link>
      <!-- Programmatic Navigation/Routing -->
      <button @click="fourBtn">four</button>
    </nav>
     <router-view></router-view>
  </div>
</template>
 
<script>
export default {
  data() {
    return {
      name: "Home",
      threeObj: {
        name: "Three",
      },
    };
  },
  methods: {
    fourBtn() {
      var userId = 6789;
      this.$router.push({
        path: `four/${userId}`,
      });
    },
  },
};
</script>
 
<style lang="less" scoped>
#home-wrapper{
  nav{
    display: flex;
    a{
      flex: 1;
      background-color: antiquewhite;
      height: 50px;
      line-height: 50px;
    }
  }
}
</style>

<template>
    <div>
        <h1>{{name}}</h1>
        <ul>
            <li>
                <router-link to="/levl31">web</router-link>
            </li>
            <li>
                <router-link :to="{name:'name32'}">backend</router-link>
            </li>
            <li>
                <!-- Using named routes is more convenient in multi-level routing-->
                <router-link :to="{name:'name33'}">AI</router-link>
            </li>
            <li>
                <router-link to="/one/levl34">UI</router-link>
            </li>
            <li>
                <router-link :to="{name:'name35'}">Level 3 Router-4</router-link>
            </li>
        </ul>
        <!-- The third-level router exits the interface of the second-level router-->
        <router-view></router-view>
 
    </div>
</template>
 
<script>
    export default {
        name:'One',
        data() {
            return {
                name: "First Page"
            }
        },
        
    }
</script>
 
<style lang="less" scoped>
ul{
    list-style: none;
    display: flex;
    width: 100%;
    margin-left: -40px;
 
}
li{
    flex: 1;
    background-color: orange;
    height: 50px;
    line-height: 50px;
 
}
 
</style>

<template>
  <div>
    <h1>{{ name }}</h1>
    <button @click="changeCode">Verification code</button>
    <img :src="imgCodeUrl" alt="">
  </div>
</template>
 
<script>
export default {
  // The component's alias is convenient for viewing during Vue debugging name: "Two_zh",
  data() {
    return {
      name: "Page 2",
      imgCodeUrl:""
    };
  },
  methods: {
    // Get the verification code changeCode() {
        // /api is the proxy configuration in vue.config.js const url = "api/v1/captchas";
    // const url = "https://elm.cangdu.org/v1/captchas";
      this.axios
        .post(url, {})
        .then((res) => {
            this.imgCodeUrl =res.data.code 
          console.log("Verification code interface:",res);
        })
        .catch((e) => {
          console.log("Error:", e);
        });
    },
  },
};
</script>
 
<style lang="less" scoped>
</style>

<template>
    <div>
        <h1>{{name}}</h1>
 
    </div>
</template>
 
<script>
    export default {
        name:'three',
        data() {
            return {
                name: "Page 3"
            }
        },
        
    }
</script>
 
<style lang="less" scoped>
 
</style>

<template>
    <div>
        <h1>{{name}}</h1>
 
    </div>
</template>
 
<script>
    export default {
        name:'Four',
        data() {
            return {
                name: "Page 4"
            }
        },
        created() {
            console.log("Page 4 created:",this.$route)
        },
    }
</script>
 
<style lang="less" scoped>
 
</style>

import Vue from 'vue'
import VueRouter from 'vue-router'
import Home2 from '@/views/day/home.vue'
 
Vue.use(VueRouter)
 
const routes = [
  {
    path: "/",
    name: 'home2',
    component: Home2,
    redirect: "/one",
    children: [
      {
        path: "/one",
        name: 'One',
        component: () => import("@/views/day/one.vue"),
        children: [
          {
            path: '/levl31',
            // h creacteElement means to create a virtual Dom/label Vnode 
            // The first parameter is the tag name extension. If the component you write is also the tag name // The second parameter is the optional attribute configuration of the tag // The third parameter is the content of the tag component: {
              render(h) {
                return h("h1", "frontend")
              }
            },
          },
          {
            // /Default represents the root directory#/levl31
            // Without slash, it will be concatenated automatically#/one/levl32
            //Use named routing path: "levl32"
            name: "name32",
            component: {
              render(h) {
                return h("h1", "Backend")
                }
              },
            },
            {
              path:"/one?levl33",
              name:"name33",
              component:{
                render(h) {
                  return h("h1", "Artificial Intelligence")
                  }
              }
            },
            {
              path:"/one/levl34",
              name:"name34",
              component:{
                render(h) {
                  return h("h1","Just an artist")
                  }
              }
            },
            //Level 3 and 4 routing {
              path:"level35",
              name:"name35",
              component:()=>import("@/views/Home.vue"),
              //Fourth level routing children:[
                {
                  path:"boy",
                  name:"Boy",
                  component:()=>import("@/views/boy.vue")
                },
                {
                  path:"girl",
                  name:"Girl",
                  component:()=>import("@/views/girl.vue")
                }
 
              ]
 
            }
        ]
      },
      {
        path: "/two",
        name: 'Two',
        component: () => import("@/views/day/two.vue")
      },
      {
        path: "/three",
        name: 'Three',
        component: () => import("@/views/day/three.vue")
      },
      {
        // Optional parameter \d Numeric string will not match path: "four/:id(\\d*)?",
        name: 'Four',
        component: () => import("@/views/day/four.vue")
      },
    ]
  }
]
 
const router = new VueRouter({
  routes
})
 
export default router