events.md

Events

• Basic Usage
• Wildcard Listeners
• Using Classes As Listeners
• Queued Events
• Event Subscribers

Basic Usage

The Laravel Event class provides a simple observer implementation, allowing you to subscribe and listen for events in your application.

Subscribing To An Event

Event::listen('user.login', function($user)
{
	$user->last_login = new DateTime;

	$user->save();
});

Firing An Event

$event = Event::fire('user.login', array($user));

You may also specify a priority when subscribing to events. Listeners with higher priority will be run first, while listeners that have the same priority will be run in order of subscription.

Subscribing To Events With Priority

Event::listen('user.login', 'LoginHandler', 10);

Event::listen('user.login', 'OtherHandler', 5);

Sometimes, you may wish to stop the propagation of an event to other listeners. You may do so using by returning false from your listener:

Stopping The Propagation Of An Event

Event::listen('user.login', function($event)
{
	// Handle the event...

	return false;
});

Wildcard Listeners

When registering an event listener, you may use asterisks to specify wildcard listeners:

Registering Wildcard Event Listeners

Event::listen('foo.*', function($param, $event)
{
	// Handle the event...
});

This listener will handle all events that begin with foo.. Note that the full event name is passed as the last argument to the handler.

Using Classes As Listeners

In some cases, you may wish to use a class to handle an event rather than a Closure. Class event listeners will be resolved out of the Laravel IoC container, providing you the full power of dependency injection on your listeners.

Registering A Class Listener

Event::listen('user.login', 'LoginHandler');

By default, the handle method on the LoginHandler class will be called:

Defining An Event Listener Class

class LoginHandler {

	public function handle($data)
	{
		//
	}

}

If you do not wish to use the default handle method, you may specify the method that should be subscribed:

Specifying Which Method To Subscribe

Event::listen('user.login', 'LoginHandler@onLogin');

Queued Events

Using the queue and flush methods, you may "queue" an event for firing, but not fire it immediately:

Registering A Queued Event

Event::queue('foo', array($user));

Registering An Event Flusher

Event::flusher('foo', function($user)
{
	//
});

Finally, you may run the "flusher" and flush all queued events using the flush method:

Event::flush('foo');

Event Subscribers

Event subscribers are classes that may subscribe to multiple events from within the class itself. Subscribers should define a subscribe method, which will be passed an event dispatcher instance:

Defining An Event Subscriber

class UserEventHandler {

	/**
	 * Handle user login events.
	 */
	public function onUserLogin($event)
	{
		//
	}

	/**
	 * Handle user logout events.
	 */
	public function onUserLogout($event)
	{
		//
	}

	/**
	 * Register the listeners for the subscriber.
	 *
	 * @param  Illuminate\Events\Dispatcher  $events
	 * @return array
	 */
	public function subscribe($events)
	{
		$events->listen('user.login', 'UserEventHandler@onUserLogin');

		$events->listen('user.logout', 'UserEventHandler@onUserLogout');
	}

}

Once the subscriber has been defined, it may be registered with the Event class.

Registering An Event Subscriber

$subscriber = new UserEventHandler;

Event::subscribe($subscriber);