php檔案下載代碼

<?
       header("content-type:text/html; charset=utf-8");
       $file_name=$_GET['name']; //伺服器的真實檔案名稱
       $file_realName=urldecode($_GET['real']); //資料庫的檔案名稱urlencode編碼過的
$file_dir="upload/";
$file = fopen($file_dir . $file_name,"r"); // 開啟檔案
// 輸入檔案標籤
header( "Pragma: public" );
header( "Expires: 0" );
Header("Content-type: application/octet-stream");
Header("Accept-Ranges: bytes");
Header("Accept-Length: ".filesize($file_dir . $file_name));
Header("Content-Disposition: attachment; filename=" . iconv("UTF-8","GB2312//TRANSLIT",$file_realName));
// 輸出檔案內容
echo fread($file,filesize($file_dir . $file_name));
fclose($file);
exit;
?>