PHP Decode

<?  if(isset($_POST['export'])) 
        { 
                $query = Database::prepare("SELECT * FROM hotel_rooms"); 
                $query->execute(); 
 
                $emparray = array();//  
 
                while($row = $query->fetchAll()) 
                { 
                    $emparray[] = $row; 
                } 
 
                $res = json_encode($emparray, JSON_FORCE_OBJECT); 
 
 
                // $temp = tmpfile(''); 
                // fwrite($temp, $res); 
                // fseek($temp, 0);//          
                // echo fread($temp, 1024); //-   
                
 
                //           
                ob_end_clean(); 
 
                $file = __DIR__ . '/export.json';                 
                $file_n = fopen($file, 'w'); 
                fwrite($file_n, $res); 
                // fclose($temp); //    
 
                //       
                header('Content-Description: File Transfer'); 
                header('Content-Type: application/octet-stream'); //application/octet-stream       
                header('Content-Disposition: attachment; filename=' . basename($file)); 
                header('Content-Transfer-Encoding: binary'); 
                header('Content-Length: ' . filesize($file)); 
 
                readfile($file); 
                exit(); 
         
        } ?>