<?php function isMobile(){   $useragent=isset($_SERVER['HTTP_USER_AGENT']) ? $_SERVER['HTTP_USER_AGENT'] : '';   $useragent_commentsblock=preg_match('|\(.*?\)|',$useragent,$matches)>0?$matches[0]:'';      function CheckSubstrs($substrs,$text){    foreach($substrs as $substr)     if(false!==strpos($text,$substr)){      return true;     }     return false;   }  $mobile_os_list=array('Google Wireless Transcoder','Windows CE','WindowsCE','Symbian','Android','armv6l','armv5','Mobile','CentOS','mowser','AvantGo','Opera Mobi','J2ME/MIDP','Smartphone','Go.Web','Palm','iPAQ');  $mobile_token_list=array('Profile/MIDP','Configuration/CLDC-','160×160','176×220','240×240','240×320','320×240','UP.Browser','UP.Link','SymbianOS','PalmOS','PocketPC','SonyEricsson','Nokia','BlackBerry','Vodafone','BenQ','Novarra-Vision','Iris','NetFront','HTC_','Xda_','SAMSUNG-SGH','Wapaka','DoCoMo','iPhone','iPod');   $found_mobile=CheckSubstrs($mobile_os_list,$useragent_commentsblock) ||       CheckSubstrs($mobile_token_list,$useragent);   if ($found_mobile){    return true;   }else{    return false;   }  } if (isMobile())  echo '手机登录m.jb51.com'; else  echo '电脑登录www.jb51.com'; ?>