php实现下载

<?php
function docdownload($filename)
{
   $NomFichier = basename($filename);
   $taille=filesize($filename);
   ob_end_clean();
   header("Content-Type: application/force-download; name=/"$NomFichier/"");
   header("Content-Transfer-Encoding: binary");
   header("Content-Length: $taille");
   header("Content-Disposition: attachment; filename=/"$NomFichier/"");
   header("Expires: 0");
   header("Cache-control: private");
   header("Pragma: no-cache");
   readfile($filename);
}
docdownload("asd.doc");
?>