 
  
   
  
   
  
   
  
  $iterator = new RegexIterator(
    new DirectoryIterator(
        $dir2,
        FilesystemIterator::KEY_AS_PATHNAME
        | FilesystemIterator::CURRENT_AS_FILEINFO
        | FilesystemIterator::SKIP_DOTS
    ),
   '~[^a-d]~'
);
foreach ($iterator as $file_info) {
    $filename = $file_info->getBasename();
}; 
  
   
  
   
  
   
  
   
  
   
  
   
  
   
  
  