EventArgs is the base class for classes containing event data.
This class contains no event data. It is used by events that do not pass state information to an event handler when an event is raised. The single empty EventArgs instance can be obtained through {@link getEmptyInstance}.
@license http://www.opensource.org/licenses/lgpl-license.php LGPL @link www.doctrine-project.org @since 2.0 @version $Revision: 3938 $ @author Guilherme Blanco <guilhermeblanco@hotmail.com> @author Jonathan Wage <jonwage@gmail.com> @author Roman Borschel <roman@code-factory.org>
Expanded class hierarchy of EventArgs
class EventArgs {
/**
* @var EventArgs Single instance of EventArgs
*/
private static $_emptyEventArgsInstance;
/**
* Gets the single, empty and immutable EventArgs instance.
*
* This instance will be used when events are dispatched without any parameter,
* like this: EventManager::dispatchEvent('eventname');
*
* The benefit from this is that only one empty instance is instantiated and shared
* (otherwise there would be instances for every dispatched in the abovementioned form)
*
* @see EventManager::dispatchEvent
* @link http://msdn.microsoft.com/en-us/library/system.eventargs.aspx
* @return EventArgs
*/
public static function getEmptyInstance() {
if (!self::$_emptyEventArgsInstance) {
self::$_emptyEventArgsInstance = new EventArgs();
}
return self::$_emptyEventArgsInstance;
}
}
Name | Modifiers | Type | Description | Overrides |
---|---|---|---|---|
EventArgs:: |
private static | property | ||
EventArgs:: |
public static | function | Gets the single, empty and immutable EventArgs instance. |