thinkphp中怎么判断是手机端访问还是pc端访问?

 function isMobile()
 {
         // 如果有HTTP_X_WAP_PROFILE则一定是移动设备
     if (isset ($_SERVER['HTTP_X_WAP_PROFILE']))
     return true;

     // 如果via信息含有wap则一定是移动设备,部分服务商会屏蔽该信息
     if (isset ($_SERVER['HTTP_VIA']))
     {
     // 找不到为flase,否则为true
     return stristr($_SERVER['HTTP_VIA'], "wap") ? true : false;
     }
     // 脑残法，判断手机发送的客户端标志,兼容性有待提高
     if (isset ($_SERVER['HTTP_USER_AGENT']))
     {
         $clientkeywords = array ('nokia','sony','ericsson','mot','samsung','htc','sgh','lg','sharp','sie-','philips','panasonic','alcatel','lenovo','iphone','ipod','blackberry','meizu','android','netfront','symbian','ucweb','windowsce','palm','operamini','operamobi','openwave','nexusone','cldc','midp','wap','mobile');
         // 从HTTP_USER_AGENT中查找手机浏览器的关键字
         if (preg_match("/(" . implode('|', $clientkeywords) . ")/i", strtolower($_SERVER['HTTP_USER_AGENT'])))
             return true;
     }
         // 协议法，因为有可能不准确，放到最后判断
     if (isset ($_SERVER['HTTP_ACCEPT']))
     {
     // 如果只支持wml并且不支持html那一定是移动设备
     // 如果支持wml和html但是wml在html之前则是移动设备
         if ((strpos($_SERVER['HTTP_ACCEPT'], 'vnd.wap.wml') !== false) && (strpos($_SERVER['HTTP_ACCEPT'], 'text/html') === false || (strpos($_SERVER['HTTP_ACCEPT'], 'vnd.wap.wml') < strpos($_SERVER['HTTP_ACCEPT'], 'text/html'))))
         {
             return true;
         }
     }
             return false;//则return false;
  }