本文章采用的是 ipip 所提供的 17monipdb.datx(20190109) 文件来查询IP信息,代码来自官方github,我仅做简化与小幅优化!
IPIP 今后将不再提供 .datx 格式的数据库,因此下面的代码今后肯定会过时,如果您需要下载datx数据库,可以点击下方的链接来下载博主为您分流的文件。
打包下载,包含源码

使用方法:
17monipdb.datx文件放到主目录的/data/目录下,再新建一个ipip.php文件,复制下面的代码:
<?php

class ipip
{
    private $file;
    private $offset;
    private $index;

    public function __construct($path=null)
    {
        if(empty($path)) $path = $_SERVER['DOCUMENT_ROOT'] . "/data/17monipdb.datx";

        if (!is_file($path))
            throw new \Exception("{$path} is not exits.");

        $this->file = fopen($path, 'rb');
        if (!is_resource($this->file))
            throw new \Exception("{$path} fopen failed.");

        $this->offset = unpack('Nlen', fread($this->file, 4));
        $this->index = fread($this->file, $this->offset['len'] - 4);
    }

    public function find($ip)
    {
        if (filter_var($ip, FILTER_VALIDATE_IP, FILTER_FLAG_IPV4) === FALSE)
           return FALSE; // or throw Exception?

        $nip2 = pack('N', ip2long($ip));
        $ips = explode('.', $ip);
        $idx = (256 * $ips[0] + $ips[1]) * 4;
        $start = unpack('Vlen', substr($this->index, $idx, 4));

        $off = NULL;
        $len = NULL;

        $max = $this->offset['len'] - 262144 - 4;

        for ($start = $start['len'] * 9 + 262144; $start < $max; $start += 9) {
            $tmp = $this->index[$start] . $this->index[$start + 1] . $this->index[$start + 2] . $this->index[$start + 3];
            if ($tmp >= $nip2) {
                $off = unpack('Vlen', substr($this->index, $start + 4, 3) . "\x0");
                $len = unpack('nlen', $this->index[$start + 7] . $this->index[$start + 8]);
                break;
            }
        }

        if ($off === NULL) return FALSE;

        fseek($this->file, $this->offset['len'] + $off['len'] - 262144);

        return explode("\t", fread($this->file, $len['len']));
    }

    // 不擅长php的我只能写出这种蠢代码了 XD
    public function info($ip) {
        $info = $this->find($ip);
        if (empty($info)) {
            return "火星";
        } else {
            return implode('', array_unique($info));
        }
    }
}
之后新建一个 .htaccess,禁止此目录被访问:
order allow,deny 
deny from all
调用方法如下:
<?php
require_once $_SERVER['DOCUMENT_ROOT'] . '/data/ipip.php';
$bs = new ipip();
$ip = $_SERVER["REMOTE_ADDR"];
?>
你丫的IP是 <?php echo $ip; ?>,来自于 <?php echo $bs->info($ip) ?>
测试地址