component-emitter
Advanced tools
Package description
The component-emitter package is a simple event emitter implementation that allows objects to subscribe to events, emit events, and remove event listeners. It is often used to add observer pattern capabilities to objects, enabling event-driven programming.
Event subscription
This feature allows an object to listen for specific events using the 'on' method. When the event is emitted, the callback function is called.
const Emitter = require('component-emitter');
let emitter = new Emitter();
emitter.on('event', function(message) {
console.log(message);
});Event emission
This feature allows an object to emit an event, optionally passing arguments to the event listeners.
emitter.emit('event', 'Hello World!');One-time event subscription
This feature allows an object to listen for an event only once. After the event is emitted and the listener is invoked, the listener is removed.
emitter.once('event', function(message) {
console.log(message);
});Event unsubscription
This feature allows an object to stop listening for specific events using the 'off' method.
function listener(message) {
console.log(message);
}
emitter.on('event', listener);
emitter.off('event', listener);The 'events' package is Node.js's core EventEmitter class for managing and emitting events. It is similar to component-emitter but is built into Node.js and provides a more extensive API.
EventEmitter3 is a high-performance event emitter. It offers a similar API to component-emitter but focuses on performance and is optimized for modern JavaScript engines.
Wolfy87's EventEmitter is an implementation of the EventEmitter module found in Node.js but can be used in the browser. It has additional features like namespacing events, but it's larger in size compared to component-emitter.
Readme
Event emitter component.
$ component install component/emitter
The Emitter may also be used as a mixin. For example
a "plain" object may become an emitter, or you may
extend an existing prototype.
As an Emitter instance:
var Emitter = require('emitter');
var emitter = new Emitter;
emitter.emit('something');
As a mixin:
var Emitter = require('emitter');
var user = { name: 'tobi' };
Emitter(user);
user.emit('im a user');
As a prototype mixin:
var Emitter = require('emitter');
Emitter(User.prototype);
Register an event handler fn.
Register a single-shot event handler fn,
removed immediately after it is invoked the
first time.
event and fn to remove a listener.event to remove all listeners on that event.Emit an event with variable option args.
Return an array of callbacks, or an empty array.
Check if this emitter has event handlers.
MIT
FAQs
Simple event emitter
The npm package component-emitter receives a total of 16,342,329 weekly downloads. As such, component-emitter popularity was classified as popular.
We found that component-emitter demonstrated a healthy version release cadence and project activity because the last version was released less than a year ago. It has 33 open source maintainers collaborating on the project.
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