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<?php abstract class AbstractEvent { protected $id; private $hidden; } final class Event extends AbstractEvent implements JsonSerializable { private $value; public function __construct() { $this->id = 5; $this->value = 'abc'; } public function jsonSerialize() { return get_object_vars($this); } } $e = new Event(); echo json_encode($e);
Output for 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
Deprecated: Return type of Event::jsonSerialize() should either be compatible with JsonSerializable::jsonSerialize(): mixed, or the #[\ReturnTypeWillChange] attribute should be used to temporarily suppress the notice in /in/qR1h0 on line 20 {"id":5,"value":"abc"}
Output for 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.7, 7.2.29 - 7.2.33, 7.3.16 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30
{"value":"abc","id":5}
preferences:
187.08 ms | 403 KiB | 264 Q