pocketmine\event\player\PlayerChatEvent::getMessage PHP Method

    public function getMessage()
    {
        return $this->message;
    }

 public function onChat(PlayerChatEvent $event)
 {
     $event->setCancelled();
     $player = $event->getPlayer();
     $sub = $this->playerSubs[$player->getID()];
     $sub->onChatEvent($event->getMessage());
 }