Nodejs - this.on is not a function event emitter object inheritance

user_18309173 0
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I'm learning how to use event emitter and inheritance in nodejs. I get the error:

TypeError: this.on is not a function

My code:

const EventEmitter = require('events')

const Emitter = function () {
    EventEmitter.call(this)

    this.on('event',value => {
        console.log('Event emitted',value)
    })
}

const myEmitter = new Emitter()

What I'm doing wrong?

eventemitter node.js inheritance javascript
1 Answers

With above code you're not actually inheriting from EventEmitter. I'd just use an actual class that extends it:

const EventEmitter = require('events')

class Emitter extends EventEmitter {
    constructor() {
        super();
        this.on('event', value => {
            console.log('Event emitted', value)
        });
    }
}

const myEmitter = new Emitter();
myEmitter.emit('event', 'hello'); // logs 'Event emitted hello' to the console.
user_37616280
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