Quick Event ⚡

quick-event is a TypeScript event library that provides tools that enable your application components to communicate with each other by dispatching events and listening for them. With quick-event you can easily implement signal/slot mechanism, or observer pattern.

Quick start

Install

Install with NPM or Yarn

# npm
npm install --save quick-event
# yarn
yarn add --save quick-event

Or link to the source code directly

<script src="dist/quick-event.min.js"></script>

Name QuickEvent is ready to use and no need to import.

Or CDN

<script src="https://unpkg.com/quick-event/dist/quick-event.min.js"></script>

Name QuickEvent is ready to use and no need to import.

How to use

Using CallbackList

import { CallbackList } from 'quick-event';

const callbackList = new CallbackList();
callbackList.append(() => {
  console.log('Got callback 1.');
});
callbackList.append(() => {
  console.log('Got callback 2.');
});
callbackList.dispatch();

Using EventDispatcher

import { EventDispatcher } from 'quick-event';

const dispatcher = new EventDispatcher();

dispatcher.appendListener(3, () => {
  console.log('Got event: 3.');
});

dispatcher.appendListener('my-event', () => {
  console.log('Got event: my-event.');
});
dispatcher.appendListener('my-event, () => {
  console.log('Got another event: my-event.');
});
dispatcher.dispatch(3);
dispatcher.dispatch('my-event');

Using EventQueue

import { EventQueue } from 'quick-event';

const queue = new EventQueue();
queue.appendListener(3, (s: any, n: any) => {
  console.log(`Got event: 3, s is ${s}, n is ${n}`);
});
queue.appendListener(5, (s: any, n: any) => {
  console.log(`Got event: 5, s is ${s}, n is ${n}`);
});
queue.appendListener(5, (s: any, n: any) => {
  console.log(`Got another event: 5, s is ${s}, n is ${n}`);
});

// Enqueue the events, the first argument is always the event type.
// The listeners are not triggered during enqueue.
queue.enqueue(3, 'Hello', 38);
queue.enqueue(5, 'World', 58);

// Process the event queue, dispatch all queued events.
queue.process();

Facts and features

• Powerful
  • Supports synchronous event dispatching and asynchronous event queue.
  • Supports event filter via mixins.
  • Configurable and extensible.
• Robust
  • Supports nested event. During the process of handling an event, a listener can safely dispatch event and append/prepend/insert/remove other listeners.
  • Doesn't depend on HTML DOM. eventjs works for non-browser environment.
  • Well tested. Backed by unit tests.
• Fast
  • Much faster than HTML DOM event listener system.
  • The EventQueue can process 5M events in 1 second (5K events per millisecond, when there are 100 event in the queue).
  • The CallbackList can invoke 1M callbacks in 1 second (1000 callbacks per millisecond).

Documentation

Documentation

Run the unit tests

yarn test

Rewrite

quick-event is rewritten from wqking/eventjs.

Wang Qi(wqking) is my friend and teacher, we have developed some projects together. He's a wide-ranging, experienced developer and I've learned a lot from him.

License

The code in this project is licensed under MIT license.