Serializability.md

Enum Serializability

AbstractEnum subclass instances can be serialized with serialize() and unserialized with unserialize() without issues.

Instances can also be JSON-serialized with the built-in json_encode() provided that their value itself is JSON-serializable (which they ought to be: it is recommended to have only string/int/null enum constants).

Such JSON serializations of Enum instances can of course be unserialized with json_decode(). This will however not return an Enum instance but just their wrapped value:

<?php
class TriState extends \mle86\Enum\AbstractAutoEnum
{
    public const HIGH  = 'H';
    public const LOW   = 'L';
    public const UNDEF = 'Z';
}

$triState = new TriState(TriState::HIGH);

$unserialized = unserialize(serialize($triState));
// This is now a second instance with the same value.

$jsonUnserialized = json_decode(json_encode($triState));
// This is now the string "H" (TriState::HIGH).