如何排除某些文件夹添加到php生成的zip中

我想将index.php之类的某些文件排除在由下面的代码生成的zip中。我试过一些方法，但都不管用。 请看穿它并帮助我

$dir = './archive/';
$zip_file = 'All-file.zip';

// Get real path for our folder
$rootPath = realpath($dir);

// Initialize archive object
$zip = new ZipArchive(); 
$zip->open($zip_file, ZipArchive::CREATE | ZipArchive::OVERWRITE);

// Create recursive directory iterator
/** @var SplFileInfo[] $files */
$files = new RecursiveIteratorIterator(
    new RecursiveDirectoryIterator($rootPath),
    RecursiveIteratorIterator::LEAVES_ONLY
);

foreach ($files as $name => $file){
    // Skip directories (they would be added automatically)
    if (!$file->isDir()){
        // Get real and relative path for current file
        $filePath = $file->getRealPath();
        $relativePath = substr($filePath, strlen($rootPath) + 1);

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

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

header('Content-Description: File Transfer'); 
header('Content-Type: application/octet-stream');
header('Content-Disposition: attachment; filename='.basename($zip_file));
header('Content-Transfer-Encoding: binary');
header('Expires: 0');
header('Cache-Control: must-revalidate');
header('Pragma: public');
header('Content-Length: ' . filesize($zip_file));
readfile($zip_file);

$exclusions=array('index.php');  // add more filenames to exclusion array as needed
foreach($files as $name=>$file){
    // only process non-directories && non-excluded files
    if(!$file->isDir() && !in_array($file->getFilename(),$exclusions)){
        $filePath = $file->getRealPath();  // Get real and relative path for current file
        $relativePath = substr($filePath, strlen($rootPath) + 1);
        $zip->addFile($filePath, $relativePath);  // Add current file to archive
    }
}