In an action of a controller, one of task you'll do very often, is to retrieve HTTP parameters.

In PHP, you usually get them into $_GET, $_POST, $_REQUEST, $_FILES etc.

However, except for files uploading ($_FILES), you'll never use them. You must call one of the methods of jController.

Your module used to be reusable, so it doesn't know how to retrieve parameters. For instance, depending of how URLS are configured (router), perhaps one of parameters is inside the pathinfo or in $_GET. A form could be changed, so parameters are in $_GET instead of $_POST. More important, HTTP parameters could be changed by a plugin, without changing original PHP arrays.

With other protocols like SOAP or XML-RPC, parameters can be stored into the body of the request. The Request object of jelix extract them for you.

This is why you have one unified way to retrieve a parameter: the method param() of a controller. This is the same method for GET, POST, PUT, DELETE, SOAP, XML-RPC, JSON etc...

HTTP client-request parameters are accessible through an instance of jRequest, which is accessible from jCoordinator. For example :

 $id = $GLOBALS['gJCoord']->request->getParam('id');

Although jController provides the method param():

  $id = $this->param('id');

Fetching an undefined parameter makes param() to return null or it's second argument for example:

   $title = $this->param('title','Hello World (default title)');

jController provides a few filtering methods like intParam(), floatParam() or boolParam() which use the same arguments:

• intParam() to fetch an integer,
• floatParam() to fetch a float value,
• boolParam() returns false except if the parameter's string value is "true", "1", "on", or "yes"

Use jFilter for any other type of filtering.