无法在preUpdate奏鸣曲中获取我的旧实体

Question

Here's the deal, i'm trying to update an Entity, but i'd like to compare the state of my entity before the update with the state of my entity after the update.

I try to compare the number of Users in my entity.

For example, if i add a User, i want my code to know that, for example, i had 4 Users before update, and 5 after (and get that User for further use).

After reading different topics, i've tried doing like that in my preUpdate($object){} method

$em = this->getConfigurationPool()->getContainer()->get('doctrine')->getManager();
$original = $em->getUnitOfWork()->getOriginalEntityData($object);

But both

var_dump(count($object->getUsers()));
var_dump(count($original['users']));

Give the same value, and, according to my example, the value is 5 in both case (so the value after the update).

Is there a way i can save the old_state of my entity in a var? What am i doing wrong?

EDIT: It's not the preUpdate function of Doctrine, but the preUpdate function of SonataAdmin, don't know if they're the same.

Answer 1

Please try this in the preUpdate function:

    $em = $this->getModelManager()->getEntityManager($this->getClass());
    $original = $em->getUnitOfWork()->getOriginalEntityData($object);