| 12345678910111213141516171819202122 | // event-bus.jsconst EventBus = {  events: {} as any,  // 重新定义的 on 方法,用于注册事件监听器,现在同一个 eventName 只会保留最后注册的那个监听器  on: function (eventName: string, callback: Function) {      this.events[eventName] = callback;  },  // 用于触发事件,通知注册的监听器执行相应逻辑  emit: function (eventName: string, data: any) {      if (this.events[eventName]) {          this.events[eventName](data);      }  },  // 新增的关闭事件方法,用于移除指定事件的监听器  off: function (eventName: string) {      if (this.events[eventName]) {          delete this.events[eventName];      }  }};export default EventBus;
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