PlayerChatEvent and setRecipients

Hi all,
I've got a simple question about PlayerChatEvent and its function setRecipients. I want to prevent a player from sending and receiving messages. How can I do this? How does setRecipients work and how should I use it in this case?

Sending is easy: cancel the event
setRecipients: look at that post: https://forums.pocketmine.net/threads/correct-way-to-use-setrecipients.13352/

For sending, just cancel the PlayerChatEvent.
PlayerChatEvent::setRecipients($array);
while $array is an array out of Player Objects. For Example:

PHP:

$array = array();
foreach($this->getServer()->getOnlinePlayers() as $pl){
  if(strpos(strtolower($pl->getName()), "a"){
    array_push($array, $pl);
  }
}
$event->setRecipients($array);

in PlayerChatEvent will put every Player with an "a" in his name as a Recipient. Every Player that is not in the array $array, will not recieve the message.

1. Get all recipients.
2. For each $i as $recipient, if you want to block $recipient, unset $recipients[$i]
3. Set all recipients to your array, after iteration.

Wouldn't you need to substract 1 of the count?

Nope. PHP supports concurrent array editing during iteration. The array will be like cloned when it is passed onto foreach.
http://php.net/manual/en/control-structures.foreach.php#114759

Nevermind, misread it. Thought you wanted to count() the array and use for(), sorry I was brain AFK.

Thanks for all replies
Now I understand how it works. Maybe it was a simple English grammar related thing (I didn't know that recipients in English are same as receivers or "destinatari" in Italian so I didn't know what that function was used for )