Is there a way of initializing a codeigniter 4 Model variable once in a Controller

Question

I understand that we could autoload or load models in the constructor and use them all through the class in earlier versions of codeigniter like below:

//Declaring the variable

$this->load->model('model_name');

//Using it through the controller

$this->model_name->function();

But in codeigniter 4, is there an easier way of defining a model variable once in a Controller. The current way i know of doing that is :

//Declaring the variable

$model_var = new ModelName();

//Using it through the controller

 ????????

But as far as i have tried looking, i have to do the initializing in every function.

Answer 1

The easiest thing to do is create a property for the controller to hold an instance of the model.

CI v4 relies on an initializer function instead of a constructor to set up properties and the like. So creating something like this would follow "best practice" for a simple controller in a simple app.

<?php
namespace App\Controllers;

/**
 * Class SomeController
 *
 */

use CodeIgniter\Controller;

class SomeController extends Controller
{
    /**
     * @var ModelName instance
     */
     // $modelVar; ```edited - will throw a php syntax error```

     protected $modelVar; ```this works```

    /**
     * Initializer 
     */
    public function initController(\CodeIgniter\HTTP\RequestInterface $request, \CodeIgniter\HTTP\ResponseInterface $response, \Psr\Log\LoggerInterface $logger)
    {

        parent::initController($request, $response, $logger);

        // Load the model
        $this->modelVar = new ModelName();
    }

}

For your convenience, CI supplies /app/Controllers/BaseController.php that the above example used in part.

The idea behind BaseController was to provide a class that could be used to load resources (classes, helpers, etc) that EVERY controller in the application would need. Then each controller would extend from BaseController. The above example assumes that there isn't a need for anything else, which in real-life is unrealistic. So the above could extend BaseController too if there were a need.