main.js

//引入Vue
import Vue from "vue";
//引入App
import App from './App';//关闭Vue的生产提示
Vue.config.productionTip = false;new Vue({el:'#app',render: h => h(App),
});

App.vue

<template><div class="app"><h1>{{ msg }}</h1><School/><Student/></div>
</template><script>
import Student from "@/components/Student";
import School from "@/components/School";
export default {name: "App",components: {School,Student,},data() {return {msg: 'helloこんにちは',studentName: ''}}
}
</script><style>/*全局的样式是不需要加scoped全局共享*/.app{background: gray;padding: 5px;}
</style>

Student.vue

<template><div class="student"><h2>姓名:{{  name }}</h2><h2>性别: {{ sex }}</h2><button @click="sendStudentName">把学生名传递给school组件</button></div>
</template><script>
import pubsub from "pubsub-js";
export default {name: "Student",data(){console.log(this);return {name: '张三',sex: '男',}},methods:{sendStudentName(){// this.$bus.$emit('hello', this.name);//发布消息pubsub.publish('hello', this.name);}},
}
</script><style scoped>.student{background: orange;padding: 5px;margin-bottom: 10px;}
</style>

School.vue

<template><div class="demo"><h2>学校名称:{{  name }}</h2><h2>学校地址: {{ address }}</h2></div>
</template><script>
import pubsub from 'pubsub-js';
export default {name: "School",data(){console.log(this);return {name: 'wust university',address: '武汉科技大学'}},mounted() {// console.log('School', this);// this.$bus.$on('hello', (data) => {//   console.log(`我是School组件,我收到了数据,${data}`);// })//订阅消息 隔空对讲机喊话this.pubId = pubsub.subscribe('hello',  (name, msg) => {//注意这里写剪头函数this才不会丢console.log(`有人发布了hello消息，回调被执行,data: ${msg}`);});},beforeDestroy() {// this.$bus.$off('hello'); //销毁解绑//取消订阅pubsub.unsubscribe(this.pubId); //取消订阅}
}
</script><style scoped>/*scoped代表局部的*/.demo{background: skyblue;padding:5px}
</style>