harusnya gini kk disesuaikan dgn kebutuhan

<?php
// Tentukan folder id_file yang boleh di download
$folder = "../doc/";
if(!isset($_GET['id_file'])){
    die('tidak ada id_file yg dibuka');
}
// Lalu cek menggunakan fungsi id_file_exist
if (!file_exists($folder.$_GET['id_file'])) {
  echo "<h1>Access forbidden!</h1>
<p>&nbsp;</p>
<p> File yang anda cari tidak ada.</p>";
  exit;
}
else { // Apabila mendownload id_file di folder id_files
  header("Content-Type: octet/stream");
//===============
    $name=trim(strtolower($_GET['id_file']) );
  header("Content-Disposition: attachment; filename=\"".$name."\"");
/*
  $fp = fopen($folder.$_GET['id_file'], "r");
  $data = fread($fp, id_filesize($folder.$_GET['id_file']));
*/
    $data=file_get_contents($folder.$_GET['id_file']);
  //fclose($fp);
  print $data;
}
?>