This is a working example of making ZIPs in PHP:
$zip = new ZipArchive();
$zip_name = time().".zip"; // Zip name
$zip->open($zip_name, ZipArchive::CREATE);
foreach ($files as $file) {
echo $path = "uploadpdf/".$file;
if(file_exists($path)){
$zip->addFromString(basename($path), file_get_contents($path));
}
else{
echo"file does not exist";
}
}
$zip->close();