最笨方法自己亲测！
if (isset($_SERVER[‘HTTP_USER_AGENT‘])) {
$clientkeywords = array(‘iphone‘, ‘android‘, ‘phone‘, ‘mobile‘, ‘wap‘, ‘netfront‘, ‘java‘, ‘opera mobi‘, ‘opera mini‘,‘ucweb‘, ‘windows ce‘, ‘symbian‘, ‘series‘, ‘webos‘, ‘sony‘, ‘blackberry‘, ‘dopod‘, ‘nokia‘, ‘samsung‘,‘palmsource‘, ‘xda‘, ‘pieplus‘, ‘meizu‘, ‘midp‘, ‘cldc‘, ‘motorola‘, ‘foma‘, ‘docomo‘, ‘up.browser‘,‘up.link‘, ‘blazer‘, ‘helio‘, ‘hosin‘, ‘huawei‘, ‘novarra‘, ‘coolpad‘, ‘webos‘, ‘techfaith‘, ‘palmsource‘,‘alcatel‘, ‘amoi‘, ‘ktouch‘, ‘nexian‘, ‘ericsson‘, ‘philips‘, ‘sagem‘, ‘wellcom‘, ‘bunjalloo‘, ‘maui‘, ‘smartphone‘,‘iemobile‘, ‘spice‘, ‘bird‘, ‘zte-‘, ‘longcos‘, ‘pantech‘, ‘gionee‘, ‘portalmmm‘, ‘jig browser‘, ‘hiptop‘,‘benq‘, ‘haier‘, ‘^lct‘, ‘320x320‘, ‘240x320‘, ‘176x220‘, ‘windows phone‘);
// 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‘]))) {
echo 123;
}
}