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New Feature

Available since version 4.8.0

Installation Requirements

Enumerations require PHP version 8.1 or higher.

The BackedEnumStrategy provides bidirectional conversion between strings or integers and Backed Enums.

The code examples below will use the following backed enum, representing a genre of music:

enum Genre: string
    case Pop   = 'pop';
    case Blues = 'blues';
    case Jazz  = 'jazz';

Basic Usage

The following code example shows standalone usage without adding the strategy to a hydrator.

Create and Configure Strategy

Create the strategy passing the class name of the enum it will hydrate and extract:

$strategy = new Laminas\Hydrator\Strategy\BackedEnumStrategy(Genre::class);

Hydrate Data

$hydrated = $strategy->hydrate('blues', null);
var_dump($hydrated); // enum Genre::Blues : string("blues");

Extract Data

$extracted = $strategy->extract(Genre::Pop);
var_dump($extracted); // string(3) "pop"


The following example demonstrates hydration for a class with a property.

An example class which represents an album with a music genre:

class Album
    private ?Genre $genre;

    public function __construct(?Genre $genre = null)
        $this->genre = $genre;

    public function getGenre() : Genre
        return $this->genre;

Create Hydrator and Add Atrategy

Create a hydrator and add the BackedEnumStrategy as a strategy:

$hydrator = new Laminas\Hydrator\ReflectionHydrator();
    new Laminas\Hydrator\Strategy\BackedEnumStrategy(Genre::class)

Hydrate Data

Create an instance of the example class and hydrate data:

$album = new Album();
$hydrator->hydrate(['genre' => 'jazz'], $album);

echo $album->getGenre()->value; // "jazz"

Extract Data

$extracted = $hydrator->extract($album);

echo $extracted['genre']; // "jazz"