What's a valid PHP callback?

Yii 1.1 General Discussion
1

Hi,

in Component Event paragraph at "http://www.yiiframework.com/doc/guide/1.1/en/basics.component",

there is written:


We can attach a method to this event as follows:


$component->onClicked=$callback;

where $callback refers to a valid PHP callback

then what’s a valid PHP callback?

2

Anything on this page:

http://uk2.php.net/manual/en/language.pseudo-types.php#language.types.callback

From this page:

http://www.lornajane.net/posts/2011/Callbacks-in-PHP

If that’s what you’re asking?

Forgive me for throwing links at you, but your question got me interested in brushing up my PHP knowledge.

3

So a callback is just a reference to some method or funtion. This reference is expressed, in the first case, as an array (Object,methodeName) and, in second case, as a simple string (functionName).

It’s Right?

4

Yes, correct.

5

It’s also worth mentioning that PHP 5.3 closures also qualify as valid callbacks e.g.




$component->onClick = function() {

    echo 'Hello I'm a closure';

}