Attributes

Attributes (PHP 8.0+) provide a way to add metadata to classes, methods, properties, and functions without modifying the code itself.

Basic Syntax

Last updated: April 6, 2026 Minimum PHP Version: PHP 8.0+ Status: Stable

PHP Version Support

Feature	PHP 7.4	PHP 8.0+	PHP 8.1+	PHP 8.2+
Attributes	❌	✅	✅	✅
Class Attributes	❌	✅	✅	✅
Method Attributes	❌	✅	✅	✅
Property Attributes	❌	✅	✅	✅
Function Attributes	❌	✅	✅	✅
Parameter Attributes	❌	❌	❌	✅

<?php
#[Attribute]
class MyAttribute
{
    public function __construct(
        public string $description = ''
    ) {}
}
?>

Using Attributes

<?php
#[Attribute]
class Route
{
    public function __construct(
        public string $path,
        public string $method = 'GET'
    ) {}
}

#[Route('/users', method: 'GET')]
class UserController
{
    #[Route('/users', method: 'POST')]
    public function create(): void
    {
        // Create user
    }

    #[Route('/users/{id}', method: 'GET')]
    public function show(int $id): void
    {
        // Show user
    }
}
?>

Reading Attributes

<?php
#[Attribute]
class Route
{
    public function __construct(
        public string $path,
        public string $method = 'GET'
    ) {}
}

#[Route('/api/users')]
class UserController
{
    #[Route('/api/users/{id}', method: 'GET')]
    public function getUser(int $id): void {}
}

$reflection = new ReflectionClass(UserController::class);
$attributes = $reflection->getAttributes(Route::class);

foreach ($attributes as $attribute) {
    $route = $attribute->newInstance();
    echo $route->path; // /api/users
}
?>

Common Use Cases

Validation

<?php
#[Attribute]
class NotBlank
{
    public function __construct(
        public string $message = 'This field cannot be blank'
    ) {}
}

#[Attribute]
class MinLength
{
    public function __construct(
        public int $length,
        public string $message = ''
    ) {}
}

class UserDTO
{
    public function __construct(
        #[NotBlank]
        #[MinLength(3)]
        public string $username,

        #[NotBlank]
        #[MinLength(8)]
        public string $password
    ) {}
}
?>

Caching

<?php
#[Attribute]
class Cacheable
{
    public function __construct(
        public int $ttl = 3600,
        public string $key = ''
    ) {}
}

class ProductService
{
    #[Cacheable(ttl: 600, key: 'product_list')]
    public function getProducts(): array
    {
        // Expensive database query
        return [];
    }
}
?>

Deprecation

<?php
#[Deprecated(
    replacement: 'newMethod',
    since: '2.0'
)]
function oldMethod(): void
{
    // Old implementation
}
?>

Built-in PHP Attributes

#[ReturnTypeWillChange]

<?php
class MyArray implements ArrayAccess
{
    #[ReturnTypeWillChange]
    public function offsetGet($key) { }

    #[ReturnTypeWillChange]
    public function offsetSet($key, $value) { }

    #[ReturnTypeWillChange]
    public function offsetExists($key): bool { }

    #[ReturnTypeWillChange]
    public function offsetUnset($key) { }
}
?>

#[AllowDynamicProperties]

<?php
class StdClass
{
    #[AllowDynamicProperties]
    public string $dynamic = 'value';
}
?>

#[NoDiscard]

<?php
#[NoDiscard]
function getConfig(): Config
{
    return new Config();
}

getConfig(); // Warning: discarded return value
?>

Attribute vs PHPDoc Annotations

Feature	Attributes	PHPDoc
Syntax	Native PHP syntax	Docblock comments
Parseable at runtime	Yes	Requires reflection
IDE support	Native	Via plugins
Type checking	Yes	No
Performance	No overhead	Parsing required
Tooling support	Growing	Extensive