如何包装emitter.on(eventName)？

Question

const myEmitter = new MyEmitter();
myEmitter.on('event', (a) => {
  console.log('an event occurred! ' + a);
});
myEmitter.emit('event', "a");

我如何才能改变

myEmitter.on('event', (a) => {
   console.log('an event occurred! ' + a);
});

类似这样的东西

onEvent((a) => console.log('an event occurred! ' + a))

我希望在事件(‘myEmitter.on’)周围有一个包装器，所以我的onEvent本质上只是调用myEmitter.on('event')。这有可能吗？

Answer 1

const onEvent = cb => myEmitter.on('event', cb);

如果您想要处理不同的事件，也可以执行以下操作：

const on = (event, cb) => myEmitter.on(event, cb);
on('event', () => console.log('an event occurred!'));

Answer 2

如下所示：

const onEvent = (callback) => {
  myEmitter.on('event', callback);
};

Answer 3

您可以创建一个自定义事件，如下所示。

var createEvent = (eventName)=>(callback)=>myEmitter.on(eventName, callback);
let event1 = createEvent('event1');
event1((a)=>{
   console.log('Event Occurred!', a);
});