public function setActiveWorksheet($worksheet)
    {
        if(is_string($worksheet)){
            $worksheet = $this->worksheets[md5($worksheet)];
        }
        $this->active_worksheet = $worksheet;
        return $worksheet;

    }
public function setActiveWorksheet($worksheet)
    {
        if(is_string($worksheet)){
            $worksheet = $this->worksheets[md5($worksheet)];
        }
        $this->active_worksheet = $worksheet;
        return $worksheet;

    }
public function setActiveWorksheet ( $ worksheet ) { if ( is_string ( $ worksheet ) ) { $ worksheet = $ this -> worksheets [ md5 ( $ worksheet ) ] ; } $ this -> active_worksheet = $ worksheet ; return $ worksheet ; }
Sets the active worksheet
@param string $worksheet The name of the worksheet or a reference to the DOMElement itself
@return DOMElement The active worksheet
Sets the active worksheet