設定動態網址

main.js

import { createRouter, createWebHistory } from "vue-router";
import Home from "../views/Home.vue";

const routes = [
  {
    path: "/",
    name: "Home",
    component: Home,
  },
  {
    path: "/about",
    name: "About",
    component: () => import("../views/About.vue"),
  },
  {
    path: "/courses",
    name: "Courses",
    component: () => import("../views/Courses/index.vue"),
  },
  {
    path: "/courses/:id", // 加上:id
    name: "Courses_id",
    component: () => import("../views/Courses/_id.vue"),
  },
];

const router = createRouter({
  history: createWebHistory(process.env.BASE_URL),
  routes,
});

export default router;

設定外層的nav

useRoute: 用來獲取網址上面的參數
useRouter: 提供處理轉址相關的操作API

點擊選單，會根據路由去加上active，由於動態選單不會被加上router-link-active，所以使用監聽的方式去綁定class

App.vue

import { reactive, ref, watch } from 'vue';
import { useRoute } from 'vue-router';
export default {
  setup() {
    const route = useRoute();
    const reouteArr = reactive(['', 'about', 'courses']); // 每個選單的路由
    const index = ref(0);
    watch(
      ()=>route.path, // 取得現在的路由
      ()=>{
        reouteArr.forEach((item, idx) => {
          const rp = route.path.substr(1).split('/')[0]; // 移除斜線
          // substr() 方法返回一個字符串中從指定位置開始到指定字符數的字符。
          // split() 指定的字串分割，返回一個新Array
          if (item === rp) {
            index.value = idx;
          }
        })
      }
    )
    return { index };
  },
};

<div id="nav">
    <router-link to="/" :class="{active:index === 0}"> Home </router-link>
    |
    <router-link to="/about" :class="{active:index === 1}"> About </router-link>
    |
    <router-link to="/courses" :class="{active:index === 2}"> Courses </router-link>
  </div>
<router-view />

* {
  padding: 0;
  margin: 0;
  box-sizing: border-box;
}
html,
body {
  width: 100%;
  height: 100%;
}
#app {
  width: 100%;
  height: 100%;
  font-family: Avenir, Helvetica, Arial, sans-serif;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-align: center;
  color: #2c3e50;
}

#nav {
  padding: 30px;
  a {
    font-weight: bold;
    color: #2c3e50;
    &.active {
      color: #42b983;
    }
  }
}

內層的選單

如要切換選單時做更多的效果可以不使用router-link
router.push可以指向要去的頁面
router.push(‘/路徑’) or router.push({ path: ‘/路徑’ })
router.go(-1);回上一頁

滑鼠中鍵沒辦法讓router.push跳出視窗
可以使用router.resolve儲存路徑，再用純JS開啟路徑的視窗

/Courses/index.vue

import { useRouter } from 'vue-router';
import { onMounted, reactive } from 'vue';
import axios from "axios";
export default {
  setup() {
    const coursesList = reactive({ data:{} }); // 儲存API回來的data
    const router = useRouter();
    const goNewRouter = (id)=>{
      router.push({path: `/courses/${id}`});
    }
    // 滑鼠中鍵沒辦法讓router.push跳出視窗
    const openNewTab = (id) => {
      const saveUrl = router.resolve({ path: `/courses/${id}` }); // router.resolve可儲存路徑
      window.open(saveUrl.href);
    }

    onMounted(()=>{
      axios.get('https://vue-lessons-api.herokuapp.com/courses/list').then((res)=>{
        coursesList.data = res.data;
      })
    })
    return {
      coursesList, goNewRouter, openNewTab
    };
  },
};

如果 @click事件有兩個就要加修飾符，才知道點的是要觸發哪一個Funtion
@click.left 滑鼠左鍵 @click.middle 滑鼠中鍵

<div id="courses">
  <a class="card" v-for="item in coursesList.data" :key="item.id"
  @click.left="goNewRouter(item.id)"
  @click.middle="openNewTab(item.id)"
  >
    <img :src="item.photo" alt="" />
    <div class="content">
      <h1>{{ item.name }}</h1>
      <div class="teacher-box">
        <div class="teach-img">
          <img class="teacher" :src="item.teacher.img" alt="" />
          <p>{{ item.teacher.name }}</p>
        </div>
        <h2>NTD: {{ item.money }}</h2>
      </div>
    </div>
  </a>
</div>

#courses {
  position: fixed;
  top: 50%;
  left: 50%;
  transform: translateX(-50%) translateY(-50%);
}
a.card {
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  width: 318px;
  height: auto;
  padding: 10px;
  border-radius: 5px;
  box-shadow: 0 0 5px rgba($color: #000000, $alpha: 0.2);
  margin-bottom: 20px;
  opacity: 0.7;
  transition: opacity 0.2s;
  background-color: rgb(231, 231, 231);
  &:hover {
    opacity: 1;
  }
  > img {
    margin-right: 10px;
  }
  .content {
    > h1 {
      font-size: 14px;
      text-align: left;
    }
    .teacher-box {
      display: flex;
      justify-content: space-between;
      align-items: center;
      margin-top: 5px;
      > h2 {
        font-size: 13px;
      }
      .teach-img {
        display: flex;
        justify-content: flex-start;
        align-items: center;
        > img {
          border-radius: 25px;
          margin-right: 10px;
        }
      }
    }
  }
}

設定內頁

/Courses/_id.vue

import { useRoute, useRouter } from 'vue-router';
import { onMounted, onUnmounted, reactive, ref } from 'vue';
import axios from 'axios';
export default {
  setup() {
    const route = useRoute();
    const router = useRouter();
    const courses = reactive({ data:{} });
    const isError = ref(false);
    let timer = null;

    onMounted(()=>{
      axios.get(`https://vue-lessons-api.herokuapp.com/courses/${route.params.id}`)
      .then(res=>{
        courses.data = res.data.data[0];
      }).catch(error=>{
        isError.value = true;
        courses.data['errorMsg'] = error.response.data.error_message;
        // 設定三秒會跳回原頁面
        timer = setTimeout(()=>{
          router.push({path:'/courses'});
          // router.push('/courses')
          // router.go(-1); // 回上一頁
        }, 3000)
      })
    })
    // 離開此組件要執行的動作
    onUnmounted(()=>{
      clearTimeout(timer);
    })

    return {
      courses, isError
    };
  },
};

物件第二層初始時會是空的(undefined)，用v-if包住，等有資料時才會出現

<div>
  <div v-if="!isError">
    <h1>{{ courses.data.name }}</h1>
    <h2>NTD: {{ courses.data.money }}</h2>
    <img :src="courses.data.photo" alt="" />
    <div v-if="Object.keys(courses.data).length !== 0"><!--等有資料時才會出現-->
      <img :src="courses.data.teacher.img" alt="" /><!--物件第二層初始時會是空的-->
      <p>{{ courses.data.teacher.name }}</p>
    </div>
  </div>
  <!-- error_message -->
  <h1 v-if="isError">{{ courses.data.errorMsg }}</h1>
</div>