Importing with use

PHP course · Advanced · Lesson 28/92

Learn to import a class from another namespace with use.

Importing with use

Writing the fully qualified name every time is tiring. With use App\Models\User; you import the class; afterwards you only need to write User.

The use declaration goes after the namespace declaration and before any class definition. To import several classes, write a separate use line for each.

Fully qualified vs short name

Without use you must write the fully qualified name: new \App\Models\User(). The leading \ means start from the root namespace.

After use App\Models\User; you can write new User(). Both forms call the same class; use only improves readability.

Exercise Import and use a class with use

Inside the App\Service namespace, import App\Models\User with use. Create new User("Alex") and print the $user->name property. The demo uses braced syntax to define two namespaces in one file.

Show example solution

Write use App\Models\User;. Create with $user = new User("Alex"); and print with echo $user->name . "\n";.
Example solution:
<?php

namespace App\Models {
    class User {
        public string $name;
        public function __construct(string $name) {
            $this->name = $name;
        }
    }
}

namespace App\Service {
    use App\Models\User;
    $user = new User("Alex");
    echo $user->name . "\n";
}

Test yourself

Complete the use statement

<?php
namespace App\Service;

____ App\Models\User;

$cfg = ["role" => "admin"];
$user = new User();

Show answer

<?php
namespace App\Service;

use App\Models\User;

$cfg = ["role" => "admin"];
$user = new User();

What does use App\Models\User; do?
- It lets you use the short name User in this file only
- It permanently renames the User class
- It deletes the App\Models namespace
- It creates a new User class
Show answer

It lets you use the short name User in this file only — Correct. With use the User class is referenced by its short name in this file.
Match the use concepts

use ...;

Imports a class
new User()

Instantiates with short name
\App\Models\User

Fully qualified path
use

Import keyword

Importing with use