Wrong with Config array?

Code:

public function onJoin(PlayerJoinEvent $e){

    $el = $e->getPlayer()->getName();

    $this->conf["Players"][] = "$el";

    $this->conf->setAll($this->con);
    $this->conf->save();

}

it says

Code:

"Cannot use object of type pocketmine\utils\Config as array"

I just want to make if player join server, save join player's name in conf.yml

 

PHP:

public function onJoin(PlayerJoinEvent $e){
    $el = $e->getPlayer()->getName();
    $players = $this->conf->get("Players");
    if (!in_array($el, $players)) {
         $players[] = $el;
         $this->conf->set("Players", $players);
         $this->conf->save();
    }
}

 

but it says "in_array() expects parameter 2 to be array, bool given"

 

You didn't set "Players" on config.

PHP:

public function onJoin(PlayerJoinEvent $e){
    $el = $e->getPlayer()->getName();
    $players = $this->conf->get("Players");
    if (!$players) {
         $this->conf->set("Players", []);
         $this->conf->save();
    }
    if (!in_array($el, $players)) {
         $players[] = $el;
         $this->conf->set("Players", $players);
         $this->conf->save();
    }
}

 

I added

Code:

@mkdir ($this->getDataFolder());

$this->conf = new Config ($this->getDataFolder()."conf.yml",Config::YAML,[
                    "Players"
            ]);
            $this->con = $this->conf->getAll();

but still same

 

PHP:

public function onJoin(PlayerJoinEvent $e){

    $el = $e->getPlayer()->getName();

    $c = $this->conf->getAll();
    $c["Players"][] = "$el";
    $this->conf->setAll($c);

    $this->conf->setAll($this->con); // this will overrid your attempt to save player's name... ???
    $this->conf->save();

}