public function findByFolderId($folderId)
    {
        foreach ($this->volumes as $volume) {
            if ($volume->findFolder($folderId)) {
                return $volume;
            }
        }

        return null;
    }
public function findByFolderId($folderId)
    {
        foreach ($this->volumes as $volume) {
            if ($volume->findFolder($folderId)) {
                return $volume;
            }
        }

        return null;
    }
public function findByFolderId ( $ folderId ) { foreach ( $ this -> volumes as $ volume ) { if ( $ volume -> findFolder ( $ folderId ) ) { return $ volume ; } } return null ; }
Return volume by folder ID.

@param string $folderId

@return Volume
Return volume by folder ID .