EventDispatcher事件调度

派发事件 {#2自定义事件}

EventDispatcher::dispatch($eventName, Event $event = null)

use EventDispatcher;
EventDispatcher::dispatch('user.login');
//你也可以在抛出事件时，塞入事件对象
EventDispatcher::dispatch('user.register', new \Event($user));
EventDispatcher::dispatch('user.register', new \UserEvent($user));

绑定监听事件

EventDispatcher::addListener($eventName, $listener, $priority = 0)

* @param eventName

 \* @param  listener  可以是一个callback方法或者一个继承于Listner的对象实例
 \* @param  priority  越大越早执行

EventDispatcher::removeListener($eventName, $listener)

* @param eventName

 \* @param  listener  可以是一个callback方法或者一个继承于Listner的对象实例

EventDispatcher::hasListeners($eventName = null)

EventDispatcher::getListeners($eventName = null)

例子：

use EventDispatcher;
$listener = new KernalResponseListener();
//定义一个事件名称，触发的监听器，和一个重要指数
EventDispatcher::addListener('kernal.responese', $listener, 10);
EventDispatcher::removeListener('kernal.responese', $listener);
EventDispatcher::hasListeners('kernal.responese');

绑定多事件监听类

EventDispatcher::addSubscriber(EventSubscriberInterface $subscriber)

EventDispatcher::removeSubscriber(EventSubscriberInterface $subscriber)

$subscriber = new TestSubscriber();
EventDispatcher::addSubscriber($subscriber);
EventDispatcher::hasListeners('test.start')
EventDispatcher::hasListeners('test.stop')
EventDispatcher::hasListeners('test.doing')
EventDispatcher::dispatch('test.start');
EventDispatcher::dispatch('test.stop');
EventDispatcher::dispatch('test.doing');
EventDispatcher::removeSubscriber($subscriber);