Event Emitter

Simple EventEmitter implementation.

Install

$ npm install --save @fabiospampinato/event-emitter

Usage

import EventEmitter from '@fabiospampinato/event-emitter';

const EE = new EventEmitter ();

let called = false;

function handler () {
  called = true;
}

EE.on ( 'my-event', handler );

EE.emit ( 'my-event' );

called; // true

EE.hasHandler ( 'my-event', handler ); // true

EE.off ( 'my-event', handler );

EE.hasHandler ( 'my-event', handler ); // false

API

bindings is an object mapping each event to an array of handlers.

new EventEmitter ( bindings: bindings = {} )

Returns an instance of EventEmitter. If the optional bindings object is passed, it will be used.

.hasHandler ( event: string, handler: Function ): Boolean

Checks if an handler is bound to an event.

.get (): bindings

Returns the current bindings object.

.set ( bindings: bindings = {} ): this

Replaces the current bindings object with the provided one.

.reset (): this

Removes all the event handlers.

.on ( event: string | string[], handler: Function | Function[] ): this

Binds an handler, or an array of handlers, to an event, or an array of events.

.one ( event: string | string[], handler: Function | Function[] ): this

Same as .on, but just before the handler gets called it will .off itself.

.off ( event: string | string[], handler?: Function | Function[] ): this

Removes an handler, or an array of handlers, from an event, or an array of events.

If no handler is passed, all the handlers bound to the event, or array of events, will be removed.

.emit ( event: string | string[], ...args ): this

Emits an event, or an array of events. All the handlers bound to it/them will be called with ...args.

License

MIT © Fabio Spampinato