PHP如何识别是电脑端或手机移动端访问网站

<span style="font-size: 14px;"><?php</span><br />function isMobile(){ <br />$useragent=isset($_SERVER['HTTP_USER_AGENT']) ? $_SERVER['HTTP_USER_AGENT'] : '';<br />$useragent_commentsblock=preg_match('|\(.*?\)|',$useragent,$matches)>0?$matches[0]:'';<br />$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');<br />$mobile_token_list=array('Profile/MIDP','Configuration/CLDC-','160×160','176×220','240×240','240×320','320×240','UP.Browser','UP.Link','SymbianOS','PalmOS','PocketPC','SonyEricsson','Nokia','BlackBerry','Vodafone','BenQ','Novarra-Vision','Iris','NetFront','HTC_','Xda_','SAMSUNG-SGH','Wapaka','DoCoMo','iPhone','iPod');<br />$found_mobile=CheckSubstrs($mobile_os_list,$useragent_commentsblock)||CheckSubstrs($mobile_token_list,$useragent);<br />if($found_mobile){ <br />return true;<br />}else{ <br />return false;<br />}<br />}<br />function CheckSubstrs($substrs,$text){ <br />foreach($substrs as $substr){<br />if(false!==strpos($text,$substr)){ <br />return true;<br />} <br />return false;<br />}<br />}<br />if(isMobile()){<br />echo '手机登录 m.phpernote.com';<br />}else{<br />echo '电脑登录 www.phpernote.com';<br />}