记录php 日常使用函数

1.获取公网ip

function clientIp($type = 0, $adv = true)
{
    $type = $type ? 1 : 0;
    static $ip = null;
    if (null !== $ip) {
        return $ip[$type];
    }
    if ($adv) {
        if (isset($_SERVER['HTTP_X_FORWARDED_FOR'])) {
            $arr = explode(',', $_SERVER['HTTP_X_FORWARDED_FOR']);
            $pos = array_search('unknown', $arr);
            if (false !== $pos) {
                unset($arr[$pos]);
            }
            $ip = trim($arr[0]);
        } elseif (isset($_SERVER['HTTP_CLIENT_IP'])) {
            $ip = $_SERVER['HTTP_CLIENT_IP'];
        } elseif (isset($_SERVER['REMOTE_ADDR'])) {
            $ip = $_SERVER['REMOTE_ADDR'];
        }
    } elseif (isset($_SERVER['REMOTE_ADDR'])) {
        $ip = $_SERVER['REMOTE_ADDR'];
    }
    // IP地址合法验证
    $long = sprintf("%u", ip2long($ip));
    $ip = $long ? array($ip, $long) : array('0.0.0.0', 0);
    return $ip[$type];
}