Content-Disposition: attachment で日本語ファイル名をダウンロードさせるテスト

download_test.php

<?php
$t = isset($_GET['t']) ? $_GET['t'] : null;

$org = '此のファイル test.php';

$fn = array(
    'A: UTF-8 Raw' => 'Content-Disposition: attachment; filename="' . $org . '"',
    'B: UTF-8 URL Encoded' => 'Content-Disposition: attachment; filename="' . rawurlencode($org) . '"',
    'C: RFC 2231' => 'Content-Disposition: attachment; filename*=UTF-8\'\'' . rawurlencode($org),
    'D: UTF-8 Raw + RFC 2231' => 'Content-Disposition: attachment; filename="' . $org . '"; filename*=UTF-8\'\'' . rawurlencode($org),
    'E: UTF-8 URL Encoded + RFC 2231' => 'Content-Disposition: attachment; filename="' . rawurlencode($org) . '"; filename*=UTF-8\'\'' . rawurlencode($org),
);

if (isset($fn[$t])) {
    header('Content-Type: application/octet-stream');
    header($fn[$t]);
    header('Content-Length: ' . filesize(__FILE__));
    readfile(__FILE__);
    exit;
}
header('Content-Type: text/html; charset=UTF-8');
?>
<ul>
<?php foreach ($fn as $i => $n): ?>
<li><a href="?t=<?php echo rawurlencode($i); ?>">Download <?php echo htmlspecialchars($i); ?></a></li>
<?php endforeach; ?>
</ul>