判断浏览器类型

/**
     *  判断是否是手机访问
     */    
    protected function isMobile() {
        if(isset($_REQUEST['from_m'])) return false;
        $userAgent = $_SERVER['HTTP_USER_AGENT'];
        $os = array();
//        $os['webkit'] = preg_match('/WebKit/([d.]+)/', $userAgent) ? true : false;
        $os['android'] = preg_match('/(Android)s+([d.]+)/) || userAgent.match(/Silk-Accelerated/', $userAgent) ? true : false;
//        $os['androidICS'] = $os['android'] && preg_match('/(Android)s4/', $userAgent) ? true : false;
//        $os['ipad'] = preg_match('/(iPad).*OSs([d_]+)/', $userAgent) ? true : false;
        $os['ipod'] = preg_match('/(iPod).*OSs([d_]+)/', $userAgent) ? true : false;
        $os['iphone'] = !$os['ipad'] && preg_match('/(iPhonesOS)s([d_]+)/', $userAgent) ? true : false;
//        $os['webos'] = preg_match('/(webOS|hpwOS)[s/]([d.]+)/', $userAgent) ? true : false;
//        $os['touchpad'] = $os['webos'] && preg_match('/TouchPad/', $userAgent) ? true : false;
//        $os['ios'] = $os['ipad'] || $os['iphone'];
//        $os['ios6'] = $os['ios'] &&  preg_match('/(OS)s([6])/', $userAgent) ? true : false;
//        $os['playbook'] = preg_match('/PlayBook/', $userAgent) ? true : false;
//        $os['blackberry'] = $os['playbook'] || preg_match('/BlackBerry/', $userAgent) ? true : false;
//        $os['blackberry10'] = $os['blackberry'] && preg_match('/Safari/536/', $userAgent) ? true : false;
//        $os['chrome'] = preg_match('/Chrome/', $userAgent) ? true : false;
//        $os['opera'] = preg_match('/Opera Mobi/', $userAgent) ? true : false;
//        $os['fennec'] = preg_match('/fennec/i', $userAgent) ? true : false;
//        $os['desktop'] = !($os['ios'] || $os['android'] || $os['blackberry'] || $os['opera'] || $os['fennec'] || $os['supportsTouch']);
        
        if($os['ipod'] || $os['iphone'] || $os['android']){
            return true;
        } else {
            return false;
        }
    }