【转】php实现通过ip查询地理位置

sonyet

　　可用类及调用方法：
　　<?php
　　
/**
* IP地理位置查询类
*
* @author 马秉尧
* @version 1.5
* @copyright 2005 CoolCode.CN
*/
class IpLocation {
      /**
       * QQWry.Dat文件指针
       *
       * @var resource
       */
      var $fp;

      /**
       * 第一条IP记录的偏移地址
       *
       * @var int
       */
      var $firstip;

      /**
       * 最后一条IP记录的偏移地址
       *
       * @var int
       */
      var $lastip;

      /**
       * IP记录的总条数（不包含版本信息记录）
       *
       * @var int
       */
      var $totalip;

      /**
       * 返回读取的长整型数
       *
       * @access private
       * @return int
       */
      function getlong() {
          //将读取的little-endian编码的4个字节转化为长整型数
          $result = unpack('Vlong', fread($this->fp, 4));
          return $result['long'];
      }

      /**
       * 返回读取的3个字节的长整型数
       *
       * @access private
       * @return int
       */
      function getlong3() {
          //将读取的little-endian编码的3个字节转化为长整型数
          $result = unpack('Vlong', fread($this->fp, 3).chr(0));
          return $result['long'];
      }

      /**
       * 返回压缩后可进行比较的IP地址
       *
       * @access private
       * @param string $ip
       * @return string
       */
      function packip($ip) {
          // 将IP地址转化为长整型数，如果在PHP5中，IP地址错误，则返回False，
          // 这时intval将Flase转化为整数-1，之后压缩成big-endian编码的字符串
          return pack('N', intval(ip2long($ip)));
      }

      /**
       * 返回读取的字符串
       *
       * @access private
       * @param string $data
       * @return string
       */
      function getstring($data = "") {
          $char = fread($this->fp, 1);
          while (ord($char) > 0) {         // 字符串按照C格式保存，以\0结束
              $data .= $char;              // 将读取的字符连接到给定字符串之后
              $char = fread($this->fp, 1);
          }
          return $data;
      }

      /**
       * 返回地区信息
       *
       * @access private
       * @return string
       */
      function getarea() {
          $byte = fread($this->fp, 1);     // 标志字节
          switch (ord($byte)) {
              case 0:                      // 没有区域信息
                  $area = "";
                  break;
              case 1:
              case 2:                      // 标志字节为1或2，表示区域信息被重定向
                  fseek($this->fp, $this->getlong3());
                  $area = $this->getstring();
                  break;
              default:                     // 否则，表示区域信息没有被重定向
                  $area = $this->getstring($byte);
                  break;
          }
          return $area;
      }

      /**
       * 根据所给 IP地址或域名返回所在地区信息
       *
       * @access public
       * @param string $ip
       * @return array
       */
      function getlocation($ip) {
          if (!$this->fp) return null;             // 如果数据文件没有被正确打开，则直接返回空
          $location['ip'] = gethostbyname($ip);    // 将输入的域名转化为IP地址
          $ip= $this->packip($location['ip']);    // 将输入的IP地址转化为可比较的IP地址
                                                  // 不合法的IP地址会被转化为255.255.255.255
          // 对分搜索
          $l = 0;                          // 搜索的下边界
          $u = $this->totalip;             // 搜索的上边界
          $findip = $this->lastip;         // 如果没有找到就返回最后一条IP记录（QQWry.Dat的版本信息）
          while ($l <= $u) {               // 当上边界小于下边界时，查找失败
              $i = floor(($l + $u) / 2); // 计算近似中间记录
              fseek($this->fp, $this->firstip + $i * 7);
             $beginip = strrev(fread($this->fp, 4));      // 获取中间记录的开始IP地址
              // strrev函数在这里的作用是将little-endian的压缩IP地址转化为big-endian的格式
              // 以便用于比较，后面相同。
              if ($ip< $beginip) {        // 用户的IP小于中间记录的开始IP地址时
                  $u = $i - 1;             // 将搜索的上边界修改为中间记录减一
              }
              else {
                  fseek($this->fp, $this->getlong3());
                  $endip = strrev(fread($this->fp, 4));    // 获取中间记录的结束IP地址
                  if ($ip> $endip) {      // 用户的IP大于中间记录的结束IP地址时
                      $l = $i + 1;         // 将搜索的下边界修改为中间记录加一
                  }
                  else {                   // 用户的IP在中间记录的IP范围内时
                      $findip = $this->firstip + $i * 7;
                      break;               // 则表示找到结果，退出循环
                  }
              }
          }

          //获取查找到的IP地理位置信息
          fseek($this->fp, $findip);
          $location['beginip'] = long2ip($this->getlong());    // 用户IP所在范围的开始地址
          $offset = $this->getlong3();
          fseek($this->fp, $offset);
          $location['endip'] = long2ip($this->getlong());      // 用户IP所在范围的结束地址
          $byte = fread($this->fp, 1);     // 标志字节
          switch (ord($byte)) {
              case 1:                      // 标志字节为1，表示国家和区域信息都被同时重定向
                  $countryOffset = $this->getlong3();          // 重定向地址
                  fseek($this->fp, $countryOffset);
                  $byte = fread($this->fp, 1);     // 标志字节
                  switch (ord($byte)) {
                      case 2:              // 标志字节为2，表示国家信息又被重定向
                          fseek($this->fp, $this->getlong3());
                          $location['country'] = $this->getstring();
                          fseek($this->fp, $countryOffset + 4);
                          $location['area'] = $this->getarea();
                          break;
                      default:             // 否则，表示国家信息没有被重定向
                          $location['country'] = $this->getstring($byte);
                          $location['area'] = $this->getarea();
                          break;
                  }
                  break;
              case 2:                      // 标志字节为2，表示国家信息被重定向
                  fseek($this->fp, $this->getlong3());
                  $location['country'] = $this->getstring();
                  fseek($this->fp, $offset + 8);
                  $location['area'] = $this->getarea();
                  break;
              default:                     // 否则，表示国家信息没有被重定向
                  $location['country'] = $this->getstring($byte);
                  $location['area'] = $this->getarea();
                  break;
          }
          if ($location['country'] == " CZ88.NET") { // CZ88.NET表示没有有效信息
              $location['country'] = "未知";
          }
          if ($location['area'] == " CZ88.NET") {
              $location['area'] = "";
          }
          return $location;
      }

      /**
       * 构造函数，打开 QQWry.Dat 文件并初始化类中的信息
       *
       * @param string $filename
       * @return IpLocation
       */
      function IpLocation($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 - $this->firstip) / 7;
              //注册析构函数，使其在程序执行结束时执行
              register_shutdown_function(array(&$this, '_IpLocation'));
          }
      }

      /**
       * 析构函数，用于在页面执行结束后自动关闭打开的文件。
       *
       */
      function _IpLocation() {
          if ($this->fp) {
              fclose($this->fp);
          }
          $this->fp = 0;
      }
}
　　$mtime = explode(' ', microtime());
$starttime = $mtime[1] + $mtime[0];
　　echo "<pre>";
$ip= "202.101.111.195";
$iplocation = new IpLocation();
$location = $iplocation->getlocation($ip);
print_r($location);
　　$mtime = explode(' ', microtime());
$endtime = $mtime[1] + $mtime[0];
var_dump($endtime-$starttime);
?>