class asd
{
	private $campaigns = array();

	public function addCampaign($zxc)
	{
		$this->campaigns[] = $zxc;
	}

	public function toArray()
	{
		echo '#';
		return $this->campaigns;
	}
}

$asd = new asd();
$asd->addCampaign(1);
$asd->addCampaign(2);
$asd->addCampaign(3);

foreach($asd->toArray() as $a)
{

}