[TOC] ## 安装 ``` composer require psr/event-dispatcher ``` ## 接口 <details> <summary>Psr\event-dispatcher\EventDispatcherInterface</summary> ``` namespace Psr\EventDispatcher; /** * Defines a dispatcher for events. */ interface EventDispatcherInterface { /** * Provide all relevant listeners with an event to process. * * @param object $event * The object to process. * * @return object * The Event that was passed, now modified by listeners. */ public function dispatch(object $event); } ``` </details> <br /> <details> <summary> Psr\event-dispatcher\ListenerProviderInterface</summary> ``` namespace Psr\EventDispatcher; /** * Mapper from an event to the listeners that are applicable to that event. */ interface ListenerProviderInterface { /** * @param object $event * An event for which to return the relevant listeners. * @return iterable[callable] * An iterable (array, iterator, or generator) of callables. Each * callable MUST be type-compatible with $event. */ public function getListenersForEvent(object $event) : iterable; } ``` </details> <br /> <details> <summary> Psr\EventDispatcher\StoppableEventInterface.php</summary> ``` namespace Psr\EventDispatcher; /** * An Event whose processing may be interrupted when the event has been handled. * * A Dispatcher implementation MUST check to determine if an Event * is marked as stopped after each listener is called. If it is then it should * return immediately without calling any further Listeners. */ interface StoppableEventInterface { /** * Is propagation stopped? * * This will typically only be used by the Dispatcher to determine if the * previous listener halted propagation. * * @return bool * True if the Event is complete and no further listeners should be called. * False to continue calling listeners. */ public function isPropagationStopped() : bool; } ``` </details> <br />