Event dispatch(string $eventName, Event $event = null)

Dispatches an event to all registered listeners.

Parameters

string	$eventName	The name of the event to dispatch. The name of the event is the name of the method that is invoked on listeners.
Event	$event	The event to pass to the event handlers/listeners If not supplied, an empty Event instance is created

Return Value

Event

array getListeners(string $eventName = null)

Gets the listeners of a specific event or all listeners sorted by descending priority.

Parameters

string

$eventName

The name of the event

Return Value

array

The event listeners for the specified event, or all event listeners by event name

int|null getListenerPriority(string $eventName, callable $listener)

Gets the listener priority for a specific event.

Returns null if the event or the listener does not exist.

Parameters

string	$eventName	The name of the event
callable	$listener	The listener

Return Value

int|null

The event listener priority

bool hasListeners(string $eventName = null)

Checks whether an event has any registered listeners.

Parameters

string

$eventName

The name of the event

Return Value

bool	true if the specified event has any listeners, false otherwise

addListener(string $eventName, callable $listener, int $priority = 0)

Adds an event listener that listens on the specified events.

Parameters

string	$eventName	The event to listen on
callable	$listener	The listener
int	$priority	The higher this value, the earlier an event listener will be triggered in the chain (defaults to 0)

removeListener(string $eventName, callable $listener)

Removes an event listener from the specified events.

Parameters

string	$eventName	The event to remove a listener from
callable	$listener	The listener to remove

addSubscriber(EventSubscriberInterface $subscriber)

Adds an event subscriber.

The subscriber is asked for all the events he is interested in and added as a listener for these events.

Parameters

EventSubscriberInterface

$subscriber

removeSubscriber(EventSubscriberInterface $subscriber)

Parameters

EventSubscriberInterface

$subscriber

protected doDispatch(callable[] $listeners, string $eventName, Event $event)

Triggers the listeners of an event.

This method can be overridden to add functionality that is executed for each listener.

Parameters

callable[]	$listeners	The event listeners
string	$eventName	The name of the event to dispatch
Event	$event	The event object to pass to the event handlers/listeners