EventEmitter3 focuses on performance while maintaining a Node.js AND browser compatible interface.
npm install @matvp91/eventemitter3throw an error when you emit an error event and nobody is
newListener and removeListener events have been removed as they
setMaxListeners, getMaxListeners, prependListener and
prependOnceListener methods are not available.
fn.bind.
removeListener method removes all matching listeners, not only the
bash
$ npm install --save eventemitter3
`
CDN
Recommended CDN:
`text
https://unpkg.com/eventemitter3@latest/dist/eventemitter3.umd.min.js
`
Usage
After installation the only thing you need to do is require the module:
`js
var EventEmitter = require('eventemitter3');
`
And you're ready to create your own EventEmitter instances. For the API
documentation, please follow the official Node.js documentation:
http://nodejs.org/api/events.html
$3
We've upgraded the API of the EventEmitter.on, EventEmitter.once and
EventEmitter.removeListener to accept an extra argument which is the context
or this value that should be set for the emitted events. This means you no
longer have the overhead of an event that required fn.bind in order to get a
custom this value.
`js
var EE = new EventEmitter()
, context = { foo: 'bar' };
function emitted() {
console.log(this === context); // true
}
EE.once('event-name', emitted, context);
EE.on('another-event', emitted, context);
EE.removeListener('another-event', emitted, context);
`
$3
This module is well tested. You can run:
- npm test to run the tests under Node.js.
- npm run test-browser to run the tests in real browsers via Sauce Labs.
We also have a set of benchmarks to compare EventEmitter3 with some available
alternatives. To run the benchmarks run npm run benchmark.
Tests and benchmarks are not included in the npm package. If you want to play
with them you have to clone the GitHub repository.
Note that you will have to run an additional npm i in the benchmarks folder
before npm run benchmark`.