is::checkFieldExists

static function checkFieldExists($entityId, $fieldName)
{
	$fld = UserFieldTable::getList(array(
		'filter' => array('=ENTITY_ID' => $entityId, '=FIELD_NAME' => $fieldName),
		'limit' => 1
	))->fetch();

	return is_array($fld) && (string) $fld['FIELD_NAME'] != '';
}