织梦dedecms软件频道怎么判断是本站下载链接后再列出镜像

if (strstr($firstLink, 'xxx.net')) //xiaoxin-20120818-判断是xxx.net域名下才出现镜像 
{ //xiaoxin-20120818-判断是xxx.net域名下才出现镜像 
$firstLink = preg_replace("#http:\/\/([^\/]*)\/#i", '/', $firstLink); 
foreach($sites as $site) 
{ 
if(trim($site)=='') continue; 
list($link,$serverName,$serverType) = explode('|', $site); 
if (!empty($link_type) && $link_type != trim($serverType)) continue; 
$link = trim( preg_replace("#\/$#", "", $link) ).$firstLink; 
$downloads = getDownloads($link); 
$uhash = substr(md5($link), 0, 24); 
if($row['gotojump']==1) 
{ 
$link = $phppath."/download.php?open=2&id={$refObj->ArcID}&uhash={$uhash}"; 
} 
$temp = str_replace("~link~", $link, $tempStr); 
$temp = str_replace("~server~", $serverName, $temp); 
$temp = str_replace("~downloads~", $downloads, $temp); 
$downlinks .= $temp; 
}