PHP判断用户是否移动端访问的办法

现在有的网站是自适应的，手机端电脑端都是一个的代码页面，这样会导致添加的广告会不适应，一般广告很少会自适应的，这样就需要判断用户是否使用哪个端访问的，如果是则移动端就显示移动广告，否则就是显示电脑端广告，实现判断的方法也很简单，一个函数就搞定了。 下面就是实现判断是否手机访问的一个方法

/*
* 检测用户设备
 */
function is_mobile_request(){
    $_SERVER['ALL_HTTP'] = isset($_SERVER['ALL_HTTP']) ? $_SERVER['ALL_HTTP'] : '';
    $mobile_browser = '0';
    if(preg_match('/(up.browser|up.link|mmp|symbian|smartphone|midp|wap|phone|iphone|ipad|ipod|android|xoom)/i', strtolower($_SERVER['HTTP_USER_AGENT'])))
        $mobile_browser++;
    if((isset($_SERVER['HTTP_ACCEPT'])) and (strpos(strtolower($_SERVER['HTTP_ACCEPT']),'application/vnd.wap.xhtml+xml') !== false))
        $mobile_browser++;
    if(isset($_SERVER['HTTP_X_WAP_PROFILE']))
        $mobile_browser++;
    if(isset($_SERVER['HTTP_PROFILE']))
        $mobile_browser++;
        $mobile_ua = strtolower(substr($_SERVER['HTTP_USER_AGENT'],0,4));
        $mobile_agents = array(
            'w3c ','acs-','alav','alca','amoi','audi','avan','benq','bird','blac',
            'blaz','brew','cell','cldc','cmd-','dang','doco','eric','hipt','inno',
            'ipaq','java','jigs','kddi','keji','leno','lg-c','lg-d','lg-g','lge-',
            'maui','maxo','midp','mits','mmef','mobi','mot-','moto','mwbp','nec-',
            'newt','noki','oper','palm','pana','pant','phil','play','port','prox',
            'qwap','sage','sams','sany','sch-','sec-','send','seri','sgh-','shar',
            'sie-','siem','smal','smar','sony','sph-','symb','t-mo','teli','tim-',
            'tosh','tsm-','upg1','upsi','vk-v','voda','wap-','wapa','wapi','wapp',
            'wapr','webc','winw','winw','xda','xda-'
        );
     if(in_array($mobile_ua, $mobile_agents))
          $mobile_browser++;
     if(strpos(strtolower($_SERVER['ALL_HTTP']), 'operamini') !== false)
          $mobile_browser++;
     // Pre-final check to reset everything if the user is on Windows  
     if(strpos(strtolower($_SERVER['HTTP_USER_AGENT']), 'windows') !== false)
          $mobile_browser=0;
     // But WP7 is also Windows, with a slightly different characteristic  
     if(strpos(strtolower($_SERVER['HTTP_USER_AGENT']), 'windows phone') !== false)
          $mobile_browser++;
     if($mobile_browser>0)  
          return true;
     else
          return false;
}

<?php
if (is_mobile_request()) {
    echo '用户正在使用手机访问';
}
else {
    echo '用户电脑在线';
}
?>