zip文件夹，不使用getRealPath

I'm trying to make zip file from a folder inside my localhost server which is my computer with windows 7 OS to a host .The problem is with using getRealPath for making the zip file the zip file content would be like this "D:\xampp\htdocs\mobl\admin\downloads" but I don't want those folders inside my zip file. How should I make zip file without those folders and just the target folder ?

this is the code I'm using to zip the folder

enter code here

$zip = new ZipArchive;

$zip->open('downloads/'.$zipname,ZipArchive::CREATE);

// Initialize empty "delete list"
$filesToDelete = array();

// Create recursive directory iterator
$files = new RecursiveIteratorIterator(new RecursiveDirectoryIterator($rootPath),
    RecursiveIteratorIterator::LEAVES_ONLY);

foreach($files as $name => $file) {
    // Get real path for current file
    $filePath = $file->getRealPath();

    // Add current file to archive
    $zip->addFile($filePath);
}

// Zip archive will be created only after closing object
$zip->close();

Thanks