Event_Dispatcher::addObserver() – Add a new observer.


require_once 'Event/Dispatcher.php';

void Event_Dispatcher::addObserver ( mixed $callback , string $nName = EVENT_DISPATCHER_GLOBAL , string $class = '' )


Adds a new observer to the dispatcher.

Observers are PHP callbacks. That means you may either pass a function name as a string or an array containing an object or class and a method to call.

The callback is used as a signature for the observer, which allows you to remove it by passing the exact same parameters to removeObserver().


  • mixed $callback

    Callback to notity, may either be a string containing the name of a global function or an array containing class or object and the name of the method to call.


    Acts as a filter: notify the observer only if the notification name matches the name passed in this parameter. Use EVENT_DISPATCHER_GLOBAL if the observer should be notified regardles of the notification name.

  • string $class = ''

    Acts as a filter: notify the observer only if the sender of the notification matches the class passed in this parameter.

Return value



This function can not be called statically.

Get the name of the dispatcher. (Previous) Remove an observer. (Next)
Last updated: Sat, 16 Feb 2019 — Download Documentation
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