Controllers

Controllers are classes that handle HTTP requests, interact with models, and return responses or views. They provide better organization than defining all logic in route closures, especially for larger applications.

Creating a Controller

A basic controller class should extend the base Controller class:

<?php
class UserController extends Controller
{
    // Method to show a user profile
    public function profile($id)
    {
        echo "User Profile ID: " . $id;
    }
}

Explanation:

The class must extend Controller.
Each public method can be mapped to a route.
Parameters in the method correspond to route dynamic segments.

Mapping Routes to Controller Methods

You can map a route to a controller method instead of a closure: Navigate to app/config/routes

<?php
$router->get('/user/{id}', 'UserController::profile');

> The `::` symbol separates the controller class and the method name.

Controller Constructor

Controllers can have a constructor to initialize shared resources:

<?php
class UserController extends Controller
{
    public function __construct()
    {
            parent::__construct();
            $this->call->library('session');
    }

    public function profile($id)
    {
        echo "User ID: " . $id;
    }
}

Use case: loading libraries, models, or middleware that will be used across multiple methods.

Returning Views from Controllers

Controllers can return HTML views using the view method:

<?php
public function profile($id)
{
    $data['user'] = $this->UserModel->find($id);
    $this->view('user/profile', $data);
}

$data is an associative array passed to the view.
The view() method renders the specified template file.

Tips and Best Practices

Use controllers for complex routes and logic.
Keep each controller focused on a specific resource or feature (e.g., UserController, PostController).
Use models for database operations, views for presentation, and controllers to coordinate them (MVC pattern).