PHP 判断用户是否为移动端访问

直接上代码：

function wp_is_mobile()
{
    static $is_mobile = null;

    if (isset($is_mobile)) {
        return $is_mobile;
    }

    if (empty($_SERVER["HTTP_USER_AGENT"])) {
        $is_mobile = false;
    } elseif (
        strpos($_SERVER["HTTP_USER_AGENT"], "Mobile") !== false ||
        strpos($_SERVER["HTTP_USER_AGENT"], "Android") !== false ||
        strpos($_SERVER["HTTP_USER_AGENT"], "Silk/") !== false ||
        strpos($_SERVER["HTTP_USER_AGENT"], "Kindle") !== false ||
        strpos($_SERVER["HTTP_USER_AGENT"], "BlackBerry") !== false ||
        strpos($_SERVER["HTTP_USER_AGENT"], "Opera Mini") !== false ||
        strpos($_SERVER["HTTP_USER_AGENT"], "Opera Mobi") !== false
    ) {
        $is_mobile = true;
    } else {
        $is_mobile = false;
    }
    return $is_mobile;
}