EventEmitter

Install

composer require tbht/php-events

Usage

add_listener

use Press\Utils\Events;

$ee = new Events();

$ee->add_listener('foo', function () {
    echo "this is a listener for php \n";
});

// the same as $ee->on()
$ee->on('foo', function () {
    echo "this is a listener for php \n";
});

$ee->emit('foo');

// the same as
$ee->emit_event('foo');

remove_listener

string

use Press\Utils\Events;

$ee = new Events();

$bar_listener = function ($arg) {
  var_dump($arg);
};

$ee->add_listener('bar', $bar_listener);

$ee->remove_listener('bar', $bar_listener);

regular expression

use Press\Utils\Events;

$ee = new Events();
$fn1 = function () {};
$fn2 = function () {};
$fn3 = function () {};
$fn4 = function () {};
$fn5 = function () {};

$ee->add_listeners([
  'foo' => [$fn1, $fn2, $fn3, $fn4, $fn5],
  'bar' => [$fn1, $fn2, $fn3, $fn4, $fn5],
  'baz' => [$fn1, $fn2, $fn3, $fn4, $fn5]
]);

$ee->remove_listener('/ba[rz]/', $fn3);

assert(
  [$fn5, $fn4, $fn2, $fn1] === $ee->flatten_listeners($ee->get_listeners('bar'))
);

add_once_listener

use Press\Utils\Events;

$ee = new Events();
$counter = 0;

$bar_listener_once = function ($counter) use (&$counter) {
  $counter++;
};

$ee->add_once_listener('foo', $bar_listener_once);

$ee->emit('foo');
$ee->emit_event('foo');

assert($counter === 1, 'the counter should be 1');

get_listeners

use Press\Utils\Events;

$fn1 = function () {
    var_dump('this is first fn');
};

$fn2 = function () {
    var_dump('this is second fn');
};

$ee = new Events();
$ee->add_listeners('foo', $fn1)
   ->add_listeners('foo', $fn2);

// listeners is an array
$listeners = $ee->get_listeners('foo');
$listeners = $ee->flatten_listeners($listeners);
var_dump($listeners);

Advance Usage

remove listeners with regex

use Press\Utils\Events;

$ee = new Events();

$fn1 = function () {};
$fn2 = function () {};
$fn3 = function () {};
$fn4 = function () {};
$fn5 = function () {};

$ee->add_listeners([
  'foo' => [$fn1, $fn2, $fn3, $fn4, $fn5],
  'bar' => [$fn1, $fn2, $fn3, $fn4, $fn5],
  'baz' => [$fn1, $fn2, $fn3, $fn4, $fn5]
]);

$ee->remove_listener('/ba[rz]/', $fn3);

$foo_list = $ee->get_listeners('foo');
$bar_list = $ee->get_listeners('bar');
$baz_list = $ee->get_listeners('baz');

count($foo_list) === 0;
count($bar_list) === 0;
count($baz_list) === 0;

get listeners as key-value

$ee = new Events();
$ee->add_listener('bar', function () {});
$ee->add_listener('baz', function () {});

$listeners = $ee->get_listeners_wrapper('/ba[rz]/');

count($listeners['bar']) === 1;
count($listeners['baz']) === 1;