Disable drop gamemode?

Tell me how to prevent all players in the creative from throwing things away?

 

Cancel PlayerItemDropEvent if the player is in creative.

 

and how to do it?

 

I already told you how to do it?

 

PHP:

public function onDrop(PlayerDropItemEvent $event){
    $player = $event->getPlayer();
    if($player->isCreative()) $event->setCancelled();
}

 

No need to define $player. Use $event->getPlayer()->isCreative() instead.

 

True, but this is to make things more laid out and plain in sight for OP