<?php   
   $the_host = $_SERVER['HTTP_HOST'];//取得當(dāng)前域名   
   $request_uri = isset($_SERVER['REQUEST_URI']) ? $_SERVER['REQUEST_URI'] : '';//判斷地址后面是否有參數(shù)   
   if($the_host == 'dedecms51.com')//把這里的域名換上你想要的   
   {   
       header('HTTP/1.1 301 Moved Permanently');//發(fā)出301頭部   
       header('Location: http://www.dedecms51.com'.$request_uri);//跳轉(zhuǎn)到你希望的地址格式   
    }  
?>