PHP Upload and Extract Zip

I'm trying to run a script that allows the upload of a .zip and extracts the contents. I grabbed a sample code online that is supposed to work and added a class at the beginning b/c my ISP doesn't have the zip functionality compiled in correctly.

I've left a big comment in the middle where I'm getting stuck. Not sure if this has anything to do with it running on IIS?

The .zip file gets uploaded where I'd expect it to, and I'm manually able to ftp it back and extract the files. I'm looking to extract the files here, loop over them, if they're image files, then add them to a database of gallery images... first things first though. Need to understand why I'm not seeing the contents of the zip...

<?php // need this bc of ISP settings
require($_SERVER['DOCUMENT_ROOT']."/_classes/ZipArchive.php");
?><?php
if($_FILES["zip_file"]["name"]) {
    $filename = $_FILES["zip_file"]["name"];
    $source = $_FILES["zip_file"]["tmp_name"];
    $type = $_FILES["zip_file"]["type"];

    $name = explode(".", $filename);
    $accepted_types = array('application/zip', 'application/x-zip-compressed', 'multipart/x-zip', 'application/x-compressed');
    foreach($accepted_types as $mime_type) {
         if($mime_type == $type) {
             $okay = true;
             break;
          } 
    }
    $continue = strtolower($name[1]) == 'zip' ? true : false;
    if(!$continue) {
        $message = "The file you are trying to upload is not a .zip file. Please try again.";
    }

    // I set up the _TEST dir with 777 permissions
    $target_path = $_SERVER['DOCUMENT_ROOT']."/_TEST/".$filename;
    if(move_uploaded_file($source, $target_path)) {
        $z开发者_运维问答ip = new ZipArchive();
        $x = $zip->open($target_path);

        // **********************************************************
        // $x returns an error here
        // code: ER_OPEN
        // http://php.net/manual/en/function.ziparchive-open.php
        // Not sure why?????
        // **********************************************************

        if ($x === true) {
           $zip->extractTo($_SERVER['DOCUMENT_ROOT']."/_TEST/");
           $zip->close();
           unlink($target_path);
           $message = "Your .zip file was uploaded and unpacked.";
        }
        else {
           $message =  'failed';
        }
    } else {    
        $message = "There was a problem with the upload. Please try again.";
    }
}
?>

Not a solution but a workaround: do you have the control of the machine? If so, install 7-zip (on Windows) or unzip, use system('unzip ...') or system('7z ...') to extract the zip archive.

ISP installed the necessary components for zip to work so all is well now. Thanks @timdream for an alternative approach.