EventBus组件通信

EventBus组件通信,请问以下代码是什么意思


export class Bus {
  private static list: { [key: string]: Array<Function> } = {};

  public static $on(name: string, fn: Function) {
    this.list[name] = this.list[name] || [];
    this.list[name].push(fn);
  }

  public static $emit(name: string, data?: unknown) {
    if (this.list[name]) {
      this.list[name].forEach((fn: Function) => {
        fn(data);
      });
    }
  }

  public static $off(name: string) {
    if (this.list[name]) Reflect.deleteProperty(this.list, name);
  }
}

理解为list是一个bus公交车
$on是公交乘务员,监听:上车人员(name),还有刷卡(fn)
$emit是人员上车,做的操作是刷卡(fn),带了data

$on负责监听了$emit对应的人员(name)数据变化,进行后续fn操作

$off 就是人到站了,下车了