How to create a compressed zip file using php

<?php
function create_compressed_zip($files = array(),$destination = '',$overwrite = false) {
//if the zip file already exists and overwrite is false, return false
if(file_exists($destination) && !$overwrite) { return false; }
$valid_files = array();
//if files passed in...
if(is_array($files)) {
//cycle through each file
foreach($files as $file) {
//make sure the file exists
if(file_exists($file)) {
$valid_files[] = $file;
}
}
}
//if we have files...
if(count($valid_files)) {
//create the archive
$zip = new ZipArchive();
if($zip->open($destination,$overwrite ? ZIPARCHIVE::OVERWRITE : ZIPARCHIVE::CREATE) !== true) {
return false;
}
//add the files
foreach($valid_files as $file) {
$zip->addFile($file,$file);
}
$zip->close();
//check to make sure the file exists
return file_exists($destination);
}
else
{
return false;
}
}
$myfiles=array('Chrysanthemum.jpg', 'Desert.jpg', 'Hydrangeas.jpg');
echo create_compressed_zip($myfiles, 'zipfile.zip', true)."hti";
?>