Create a Custom EventEmitter

Question

Create a custom EventEmitter in Node.js that listens to an event and executes a callback when the event is triggered.

Coding Answer

const EventEmitter = require("events");

// Create custom emitter
const myEmitter = new EventEmitter();

// Listen to event
myEmitter.on("greet", (name) => {
  console.log("Hello " + name);
});

// Emit event
myEmitter.emit("greet", "Manaswini");

Preview

Run the file using Node.js:

node app.js

👉 Output in terminal:

Hello Manaswini

Explanation

EventEmitter is a core module in Node.js
on() is used to listen to events
emit() is used to trigger events
Custom events help in building scalable applications