Strategies

BackedEnum

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"

Example

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 Strategy

Create a hydrator and add the BackedEnumStrategy as a strategy:

$hydrator = new Laminas\Hydrator\ReflectionHydrator();
$hydrator->addStrategy(
    'genre',
    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"