第一種：在index中建立好router例項，直接在main.js中引入
main.js
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import Vue from 'vue'
import App from './App.vue'
import Router from 'vue-router'
import router from './router/index.js'
Vue.config.productionTip = false

new Vue({
	router,//錯誤3：此處引入的例項名必須為router，否則會報錯
  render: h => h(App),
}).$mount('#app')
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index.js
 

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import Vue from 'vue'
import Router from 'vue-router'
import HelloWorld from '../components/HelloWorld.vue'
Vue.use(Router)
const router = new Router({
	mode:"history",
	routes:[
		{
			path:'/',
			redirect:HelloWorld
		},
	{
		path:'/HelloWorld',
		name:'HelloWorld',
		component:HelloWorld
	}
	]
})
export default router   //錯誤1：export default {router}，頁面不顯示（export default用法出錯：
 
https://blog.csdn.net/hsany330/article/details/81001603）
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第二種：將routes單獨引入，在main.js中建立router例項
main.js
..................................
import Vue from 'vue'
import App from './App.vue'
import Router from 'vue-router'
import routes from './router/index.js'
Vue.config.productionTip = false

Vue.use(Router)
const router = new Router({
	mode:"history",
	routes:routes
})

new Vue({
	router,
  render: h => h(App),
}).$mount('#app')
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index.js
 

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import Vue from 'vue'
import Router from 'vue-router'
import HelloWorld from '../components/HelloWorld.vue'

const routes = [
		{
			path:'/',
			redirect:HelloWorld
		},
	{
		path:'/HelloWorld',
		name:'HelloWorld',
		component:HelloWorld
	}
	]
export default routes  
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APP.vue
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<template>
  <div id="app">
    <img alt="Vue logo" src="./assets/logo.png">
<router-link to="/HelloWorld">你好</router-link>
<router-view ></router-view> //錯誤2：不寫<router-view>，頁面不顯示
  </div>
</template>

<script>
export default {
  name: 'app',
  components: {},
  created() {
  	console.log(this.$route);
	console.log(this.$router);
  }
}
</script>
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