👀 Views: 108 💬 Answers: 1 📅 Created: 2025-06-06

php json datetime serialization PHP

I'm converting an old project and I'm maintaining legacy code that I'm working with a strange scenario when trying to serialize a custom object that contains a `DateTimeImmutable` property... The question arises when I attempt to serialize the object using `json_encode`, and I receive the following behavior: `JSON_ERROR_UNSUPPORTED_TYPE`. I need to seem to figure out why this is happening since `DateTimeImmutable` is supposed to be serializable. Here's a simplified version of my code: ```php class Event { private DateTimeImmutable $eventDate; public function __construct(DateTimeImmutable $eventDate) { $this->eventDate = $eventDate; } public function getEventDate(): DateTimeImmutable { return $this->eventDate; } } $event = new Event(new DateTimeImmutable('2023-10-15')); $json = json_encode($event); if (json_last_error() !== JSON_ERROR_NONE) { echo 'Serialization behavior: ' . json_last_error_msg(); } ``` I have also tried implementing the `JsonSerializable` interface in my custom class, like so: ```php class Event implements JsonSerializable { private DateTimeImmutable $eventDate; public function __construct(DateTimeImmutable $eventDate) { $this->eventDate = $eventDate; } public function jsonSerialize() { return [ 'eventDate' => $this->eventDate->format('Y-m-d H:i:s') ]; } } ``` But this still results in the same serialization behavior. I've confirmed that both the PHP version and the extensions for JSON are up to date. Is there something I'm missing here? Shouldn't `DateTimeImmutable` be properly handled when implementing `JsonSerializable`? Any help would be appreciated! My development environment is Windows 11. I'm open to any suggestions. Any help would be greatly appreciated! My development environment is Ubuntu 20.04. I'm open to any suggestions. I'm on Windows 10 using the latest version of Php. Has anyone dealt with something similar?