Happy Coders

Namespaces in PHP are used to group classes, functions, and constants under a unique name to avoid name conflicts. They allow you to organize code in a modular and maintainable way, especially in large applications. Namespaces are declared using the namespace keyword at the top of a PHP file. They are useful when combining multiple libraries or creating reusable components. You can access namespaced elements using the use statement or fully qualified names.

1. Declare a Namespaced Class

<?php
namespace App\Controllers;

class HomeController {
    public function index() {
        echo "Welcome to HomeController";
    }
}

File Name:  HomeController.php

2. Use a Namespaced Class with use

<?php
require 'App/Controllers/HomeController.php';

use App\Controllers\HomeController;

$controller = new HomeController();
$controller->index();

File Name: index.php or any main script like test.php

3. Use Without use Keyword

<?php
require 'App/Controllers/HomeController.php';

$controller = new \App\Controllers\HomeController();
$controller->index();

File Name: index.php (or main.php, etc.)

4. Use Alias with as

<?php
require 'App/Controllers/HomeController.php';

use App\Controllers\HomeController as Home;

$home = new Home();
$home->index();

File Name: index.php or alias-test.php

Full Example Folder Structure:

project-root/
│
├── index.php                  ← Calls the controller
│
└── App/
    └── Controllers/
        └── HomeController.php ← Namespaced class

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