javascript-pour-les-jedis-episode-1-snippet-17.js

class Foo {
	constructor() {
  		this.counter = 0;
	}
	inc() {
		this.counter += 1;
		console.log(this);
	};
};

var foo = new Foo();
var element = document.querySelector('#foo');

// cas #1
element.addEventListener('click', foo.inc); //=> this === element

// cas #2
element.addEventListener('click', () => foo.inc() ); //=> this === foo

// cas #3
element.addEventListener('click', foo.inc.bind(foo)); //=> this === foo