写一个eventBus.js：

export default class eventBus{constructor() {this.events = {};}on(eventName, callback) {if (typeof callback !== "function") {throw "请传入监听函数";}if (!this.events[eventName]) {this.events[eventName] = [];}this.events[eventName].push(callback);}emit(eventName, ...args) {if (this.events[eventName]) {this.events[eventName].forEach((cb) => {cb.call(this, ...args);});}}off(eventName, callback) {if (this.events[eventName]) {if (callback) {var index = this.events[eventName].indexOf(callback);if (index > -1) {this.events[eventName].splice(index, 1);}} else {this.events[eventName].length = 0;}}}
}

main.js引入eventBus ,全局挂载$Bus实例：

import eventBus from "@/utils/eventBus";
Vue.prototype.$Bus= new eventBus();

vue组件内使用示例：

//监听事件
this.$Bus.on("pageA/upload", () => {this.show = true;
});
//触发事件
this.$Bus.emit("pageA/upload", true);
//卸载事件
this.$Bus.off("pageA/upload");