CryptoField::encrypt

public function encrypt($data)
{
	if($data == '')
	{
		//is empty data still a secret?
		return $data;
	}
	try
	{
		//encrypt the data
		$value = static::$cipher->encrypt($data, $this->cryptoKey);
		return base64_encode($value);
	}
	catch(Security\SecurityException $e)
	{
		trigger_error("Error on encrypting the field {$this->getEntity()->getName()}.{$this->getName()}: {$e->getMessage()}", E_USER_WARNING);
		return null;
	}
}