<?php
 $files = scandir($_REQUEST['folder']);
 # create new zip opbject
 $zip = new ZipArchive();

 # create a temp file & open it
 $tmp_file = tempnam('.','');
 $zip->open($tmp_file, ZipArchive::CREATE);

 # loop through each file
 foreach($files as $file){
if($file!="."){


     # download file
     $download_file = file_get_contents($file);

     #add it to the zip
     $zip->addFromString(basename($file),$download_file);
    }
 }

 # close zip
 $zip->close();

 # send the file to the browser as a download
 header('Content-disposition: attachment; filename=backupdati.zip');
 header('Content-type: application/zip');
 readfile($tmp_file);

?>