dedecms下载模块中怎么添加下载方式

<?php

<script src="http://pstatic.xunlei.com/js/webThunderDetect.js"></script>

require("encode.inc");

else if($open==1){ 
$link = base64_decode($link); 
echo "<script language=&#39;javascript&#39;>location=\"$link\";</script>"; 
exit();

else if($open==1){ 
$link = base64_decode($link); 
$Url = ("http://jb51.net/url".$link); 
$thunderUrl = ThunderEncode($Url); 
echo "<script>OnDownloadClick(&#39;".$thunderUrl."&#39;,&#39;&#39;,location.href,&#39;你的联盟id&#39;,2,&#39;&#39;)</script>"; 
exit(); 
}