经典教程-emlog显示IP地理地址的两种方法

emlog系统存储了评论人的IP地址，有的时候，需要显示该IP的真实地理地址，可以通过以下两种方法获得。 

一、本地获得IP地理地址。通过本地查找本地IP数据库（纯真版）来获得，IP数据库可以到http://www.cz88.net/下载安装后，在安装目录里把qqwry.dat文件提取出来放到emlog根目录即可。 (保证与index.php同在一个目录中)

在module.php中添加以下代码： 

<?php
//获取IP地理地址
$data = '254.254.254.254';
class IpLocation {
     var $fp;
     var $firstip;
     var $lastip;
     var $totalip;
         
     function getlong() {
        $result = unpack('Vlong', fread($this->fp, 4));
        return $result['long'];
     }

    function getlong3() {
        $result = unpack('Vlong', fread($this->fp, 3).chr(0));
        return $result['long'];
     }

     function packip($ip) {
        return pack('N', intval(ip2long($ip)));
     }
         
     function getstring($data = "") {
        $char = fread($this->fp, 1);
        while (ord($char) > 0) {
            $data .= $char;
            $char = fread($this->fp, 1);
        }
        return $data;
     }
         
     function getarea() {
        $byte = fread($this->fp, 1);
        switch (ord($byte)) {
            case 0:
               $area = "";
               break;
            case 1:
            case 2:
               fseek($this->fp, $this->getlong3());
               $area = $this->getstring();
               break;
            default: 
               $area = $this->getstring($byte);
               break;
        }
        return $area;
        }
         
     function getlocation($ip) {
        
        if (!$this->fp) return null;
        $location['ip'] = gethostbyname($ip); 
        $ip = $this->packip($location['ip']);
        $l = 0; 
        $u = $this->totalip;
        $findip = $this->lastip;
        while ($l <= $u) { 
            $i = floor(($l + $u) / 2); 
            fseek($this->fp, $this->firstip + $i * 7);
            $beginip = strrev(fread($this->fp, 4));
            if ($ip < $beginip) {
               $u = $i - 1;
            }
            else {
               fseek($this->fp, $this->getlong3());
               $endip = strrev(fread($this->fp, 4));
               if ($ip > $endip) {
                   $l = $i + 1; 
               }
               else {
                   $findip = $this->firstip + $i * 7;
                   break;
               }
            }
        }
        fseek($this->fp, $findip);
        $location['beginip'] = long2ip($this->getlong()); 
        $offset = $this->getlong3();
        fseek($this->fp, $offset);
        $location['endip'] = long2ip($this->getlong());
        $byte = fread($this->fp, 1); 
        switch (ord($byte)) {
            case 1: 
               $countryOffset = $this->getlong3();
               fseek($this->fp, $countryOffset);
               $byte = fread($this->fp, 1);
               switch (ord($byte)) {
                   case 2: 
                      fseek($this->fp, $this->getlong3());
                      $location['country'] = $this->getstring();
                      fseek($this->fp, $countryOffset + 4);
                      $location['area'] = $this->getarea();
                      break;
                   default: 
                      $location['country'] = $this->getstring($byte);
                      $location['area'] = $this->getarea();
                      break;
               }
               break;
            case 2:
               fseek($this->fp, $this->getlong3());
               $location['country'] = $this->getstring();
               fseek($this->fp, $offset + 8);
               $location['area'] = $this->getarea();
               break;
            default: 
               $location['country'] = $this->getstring($byte);
               $location['area'] = $this->getarea();
               break;
        }
        if ($location['country'] == " CZNET") { 
            $location['country'] = "未知";
        }
        if ($location['area'] == " CZNET") {
            $location['area'] = "";
        }
        return $location;
     }
         
     function IpLocation($filename = "qqwry.dat") {
        $this->fp = 0;
        if (($this->fp = @fopen($filename, 'rb')) !== false) {
            $this->firstip = $this->getlong();
            $this->lastip = $this->getlong();
            $this->totalip = ($this->lastip - $this->firstip) / 7;
            register_shutdown_function(array(&$this, '_IpLocation'));
        }
     }
         
     function _IpLocation() {
        if ($this->fp) {
            fclose($this->fp);
        }
        $this->fp = 0;
     }
}

function getaddress($myip){
$ipOrDomain=$myip;
$iplocation = new IpLocation();
$location = $iplocation->getlocation($ipOrDomain);
$address=mb_convert_encoding($location['country'].$location['area'], "utf-8", "gbk");
return $address;
}
?>