Doctrine_manual-1-2-en

Chapter 22: Event Listeners 310
The above example will output the current date as PHP knows it.
Each listener and hook method takes one parameter Doctrine_Event object.
Doctrine_Event object holds information about the event in question and can alter the
execution of the listened method.
For the purposes of this documentation many method tables are provided with column named
params indicating names of the parameters that an event object holds on given event. For
example the preCreateSavepoint event has one parameter with the name of the created
savepoint, which is quite intuitively named as savepoint.
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Connection Listeners
Connection listeners are used for listening the methods of Doctrine_Connection and its
modules (such as Doctrine_Transaction). All listener methods take one argument
Doctrine_Event which holds information about the listened event.
Creating a New Listener
There are three different ways of defining a listener. First you can create a listener by making
a class that inherits Doctrine_EventListener:
class MyListener extends Doctrine_EventListener
{
public function preExec(Doctrine_Event $event)
{
}
}
Note that by declaring a class that extends Doctrine_EventListener you don't have to
define all the methods within the Doctrine_EventListener_Interface. This is due to a
fact that Doctrine_EventListener already has empty skeletons for all these methods.
Sometimes it may not be possible to define a listener that extends
Doctrine_EventListener (you might have a listener that inherits some other base class).
In this case you can make it implement Doctrine_EventListener_Interface.
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class MyListener implements Doctrine_EventListener_Interface
{
public function preTransactionCommit(Doctrine_Event $event) {}
public function postTransactionCommit(Doctrine_Event $event) {}
public function preTransactionRollback(Doctrine_Event $event) {}
public function postTransactionRollback(Doctrine_Event $event) {}
public function preTransactionBegin(Doctrine_Event $event) {}
public function postTransactionBegin(Doctrine_Event $event) {}
public function postConnect(Doctrine_Event $event) {}
public function preConnect(Doctrine_Event $event) {}
public function preQuery(Doctrine_Event $event) {}
public function postQuery(Doctrine_Event $event) {}
public function prePrepare(Doctrine_Event $event) {}
public function postPrepare(Doctrine_Event $event) {}
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