Cakephp beforeFilter vs constructor

Question

I am new to cakephp. I found a largely used method

beforeFilter() 

My question is, how it's differ from a class constructor? What if i called

parent::beforeFilter();

from constructor instead of beforeFilter(); I just want to know what if i write the same code in

public function __construct() {
   // Code here
} 

instead of

public function beforeFilter() {
}

Thanks

Answer 1

construct() is for construction, to load things you need.

__construct( ) public Constructor

Parameters: ComponentCollection $collection A ComponentCollection this component can use to lazy load its components

http://api.cakephp.org/2.3/class-Component.html#___construct

---

beforeFilter() executes functions that you NEED to be executed before any other action

Controller::beforeFilter() This function is executed before every action in the controller. It’s a handy place to check for an active session or inspect user permissions.

http://api.cakephp.org/2.3/class-Controller.html#_beforeFilter

Called before the controller action. You can use this method to configure and customize components or perform logic that needs to happen before each controller action.

Note: The beforeFilter() method will be called for missing actions, and scaffolded actions.

http://book.cakephp.org/2.0/en/controllers.html#request-life-cycle-callbacks

Usually you will not need a constructor as, when following CakePHP conventions there are only very few scenarios where you actually have no other option than to "force" loading something manually...

Answer 2

You can find some relevant definitions from the official CakePHP documentation at https://book.cakephp.org/1.2/en/The-Manual/Developing-with-CakePHP/Controllers.html#the-app-controller:

"Callbacks: CakePHP controllers come fitted with callbacks you can use to insert logic just before or after controller actions are rendered. beforeFilter(): This function is executed before every action in the controller. It’s a handy place to check for an active session or inspect user permissions."