Task::getFilesCount

static function getFilesCount($id)
{
	$result = array();

	if (empty($id))
	{
		return $id;
	}

	$res = BitrixDiskInternalsAttachedObjectTable::getList(array(
		'select' => array(
			'TASK_ID' => 'ENTITY_ID',
			new BitrixMainEntityExpressionField('CNT', 'COUNT(ENTITY_ID)')
		),
		'filter' => array(
			'=ENTITY_TYPE' => self::className(),
			'ENTITY_ID' => $id
		),
		'group' => array(
			'ENTITY_ID'
		)
	));
	while ($row = $res->fetch())
	{
		$result[$row['TASK_ID']] = $row['CNT'];
	}

	return is_array($id) ? $result : $result[$id];
}