How do I use event emitters in Node.js?

How do I use event emitters in Node.js?

Event emitters in Node.js allow you to handle asynchronous events. You can create an instance of the EventEmitter class and use methods like 'on' to listen for events and 'emit' to trigger them.

Can you show me a simple example?

Sure! Here's a basic example:

const EventEmitter = require('events');
const myEmitter = new EventEmitter();

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

myEmitter.emit('event');

What if I want to pass data with the event?

You can pass data as arguments to the 'emit' method. For example:

myEmitter.on('event', (data) => {
  console.log(`Event data: ${data}`);
});

myEmitter.emit('event', 'Hello, World!');

Are there any built-in events in Node.js?

Yes, Node.js has several built-in event emitters, such as 'process' and 'http.Server'. You can listen to events like 'exit' or 'request'.