It's possible to detect a text of a button in UI?

Hello, it's possib to detect what is writed in a text of a button in UI? eg: when a player tap to a button that is writen Gamer008, it returns to the player what is in there "Gamer008"? I use that Packet for UIs:

PHP:

 public function Receive(DataPacketReceiveEvent $event){
    $pk = $event->getPacket();
    $player = $event->getPlayer();
    if($pk instanceof ModalFormResponsePacket){
            if($pk->formId === ID){


 

You can store it when you are sending the form

 

Yeah, i know that, but i don't want to do that, i want to detect the text when the player taps the button.

 

I think FormAPI does that magic, I'd like to know how too

 

That's not possible if you don't save text of the button