网站判断用户访问来路设备

?php

function UserAgent(){
    $user_agent = ( !isset($_SERVER['HTTP_USER_AGENT'])) ? FALSE : $_SERVER['HTTP_USER_AGENT'];
    return $user_agent;
}

//Mobile
if ((preg_match("/(iphone|ipod|android)/i", strtolower(UserAgent()))) AND strstr(strtolower(UserAgent()), 'webkit')){
    header('Location: m/');
    exit;
}else if(trim(UserAgent()) == '' OR preg_match("/(nokia|sony|ericsson|mot|htc|samsung|sgh|lg|philips|lenovo|ucweb|opera mobi|windows mobile|blackberry)/i", strtolower(UserAgent()))){
    header('Location: m/');
    exit;
}else{//PC
    header("Location:index.php");
}
?