ASP.NET把客户机IP转换成真实地址（利用纯真 IP 数据库）

工具方法：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.IO;
using System.Text.RegularExpressions;

/// <summary>
///IPScanner 的摘要说明
/// </summary>
public class IPScanner
{
  private string dataPath;
  private string ip;
  private string country;
  private string local;
  private long firstStartIp = 0;
  private long lastStartIp = 0;
  private FileStream objfs = null;
  private long startIp = 0;
  private long endIp = 0;
  private int countryFlag = 0;
  private long endIpOff = 0;
  private string errMsg = null;


  public IPScanner()
  {
    //
    // TODO: 在此处添加构造函数逻辑
    //
  }

  public string DataPath
  {
    set { dataPath = value; }
  }

  public string IP
  {
    set { ip = value; }
  }

  public string Country
  {
    get { return country; }
  }

  public string Local
  {
    get { return local; }
  }

  public string ErrMsg
  {
    get { return errMsg; }
  }


  private int QQwry()
  {
    string pattern = "^([01]?\\d\\d?|2[0-4]\\d|25[0-5])\\." +
        "([01]?\\d\\d?|2[0-4]\\d|25[0-5])\\." +
        "([01]?\\d\\d?|2[0-4]\\d|25[0-5])\\." +
        "([01]?\\d\\d?|2[0-4]\\d|25[0-5])$";
    //string pattern = @"^([1-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])(\.([0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])){3}$";
    Regex objRe = new Regex(pattern);
    Match objMa = objRe.Match(ip);
    if (!objMa.Success)
    {
      this.errMsg = "IP格式错误";
      return 4;
    }

    long ip_Int = this.IpToInt(ip);
    int nRet = 0;
    if (ip_Int >= IpToInt("127.0.0.0") && ip_Int <= IpToInt("127.255.255.255"))
    {
      this.country = "本机内部环回地址";
      this.local = "";
      nRet = 1;
    }

    else if ((ip_Int >= IpToInt("0.0.0.0") && ip_Int <= IpToInt("2.255.255.255")) || (ip_Int >= IpToInt("64.0.0.0") && ip_Int <= IpToInt("126.255.255.255")) || (ip_Int >= IpToInt("58.0.0.0") && ip_Int <= IpToInt("60.255.255.255")))
    {
      this.country = "网络保留地址";
      this.local = "";
      nRet = 1;
    }

    objfs = new FileStream(this.dataPath, FileMode.Open, FileAccess.Read);
    try
    {
      objfs.Position = 0;
      byte[] buff = new Byte[8];
      objfs.Read(buff, 0, 8);
      firstStartIp = buff[0] + buff[1] * 256 + buff[2] * 256 * 256 + buff[3] * 256 * 256 * 256;
      lastStartIp = buff[4] * 1 + buff[5] * 256 + buff[6] * 256 * 256 + buff[7] * 256 * 256 * 256;
      long recordCount = Convert.ToInt64((lastStartIp - firstStartIp) / 7.0);
      if (recordCount <= 1)
      {
        country = "FileDataError";
        objfs.Close();
        return 2;
      }

      long rangE = recordCount;
      long rangB = 0;
      long recNO = 0;
      while (rangB < rangE - 1)
      {
        recNO = (rangE + rangB) / 2;
        this.GetStartIp(recNO);
        if (ip_Int == this.startIp)
        {
          rangB = recNO;
          break;
        }

        if (ip_Int > this.startIp)
          rangB = recNO;
        else
          rangE = recNO;
      }

      this.GetStartIp(rangB);
      this.GetEndIp();
      if (this.startIp <= ip_Int && this.endIp >= ip_Int)
      {
        this.GetCountry();
        this.local = this.local.Replace("（我们一定要解放台湾！！！）", "");
      }
      else
      {
        nRet = 3;
        this.country = "未知";
        this.local = "";
      }
      objfs.Close();
      return nRet;
    }
    catch
    {
      return 1;
    }
  }

  /// <summary>
  /// IP地址转换成Int数据
  /// </summary>
  /// <param name="ip"></param>
  /// <returns></returns>
  private long IpToInt(string ip)
  {
    char[] dot = new char[] { '.' };
    string[] ipArr = ip.Split(dot);
    if (ipArr.Length == 3)
      ip = ip + ".0";
    ipArr = ip.Split(dot);
    long ip_Int = 0;
    long p1 = long.Parse(ipArr[0]) * 256 * 256 * 256;
    long p2 = long.Parse(ipArr[1]) * 256 * 256;
    long p3 = long.Parse(ipArr[2]) * 256;
    long p4 = long.Parse(ipArr[3]);
    ip_Int = p1 + p2 + p3 + p4;
    return ip_Int;
  }

  /// <summary>
  /// int转换成IP
  /// </summary>
  /// <param name="ip_Int"></param>
  /// <returns></returns>
  private string IntToIP(long ip_Int)
  {
    long seg1 = (ip_Int & 0xff000000) >> 24;
    if (seg1 < 0)
      seg1 += 0x100;
    long seg2 = (ip_Int & 0x00ff0000) >> 16;
    if (seg2 < 0)
      seg2 += 0x100;
    long seg3 = (ip_Int & 0x0000ff00) >> 8;
    if (seg3 < 0)
      seg3 += 0x100;
    long seg4 = (ip_Int & 0x000000ff);
    if (seg4 < 0)
      seg4 += 0x100;
    string ip = seg1.ToString() + "." + seg2.ToString() + "." + seg3.ToString() + "." + seg4.ToString();
    return ip;
  }

  /// <summary>
  /// 获取起始IP范围
  /// </summary>
  /// <param name="recNO"></param>
  /// <returns></returns>
  private long GetStartIp(long recNO)
  {
    long offSet = firstStartIp + recNO * 7;
    //objfs.Seek(offSet,SeekOrigin.Begin);
    objfs.Position = offSet;
    byte[] buff = new Byte[7];
    objfs.Read(buff, 0, 7);
    endIpOff = Convert.ToInt64(buff[4].ToString()) + Convert.ToInt64(buff[5].ToString()) * 256 + Convert.ToInt64(buff[6].ToString()) * 256 * 256;
    startIp = Convert.ToInt64(buff[0].ToString()) + Convert.ToInt64(buff[1].ToString()) * 256 + Convert.ToInt64(buff[2].ToString()) * 256 * 256 + Convert.ToInt64(buff[3].ToString()) * 256 * 256 * 256;
    return startIp;
  }

  /// <summary>
  /// 获取结束IP
  /// </summary>
  /// <returns></returns>
  private long GetEndIp()
  {
    //objfs.Seek(endIpOff,SeekOrigin.Begin);
    objfs.Position = endIpOff;
    byte[] buff = new Byte[5];
    objfs.Read(buff, 0, 5);
    this.endIp = Convert.ToInt64(buff[0].ToString()) + Convert.ToInt64(buff[1].ToString()) * 256 + Convert.ToInt64(buff[2].ToString()) * 256 * 256 + Convert.ToInt64(buff[3].ToString()) * 256 * 256 * 256;
    this.countryFlag = buff[4];
    return this.endIp;
  }

  /// <summary>
  /// 获取国家/区域偏移量
  /// </summary>
  /// <returns></returns>
  private string GetCountry()
  {
    switch (this.countryFlag)
    {
      case 1:
      case 2:
        this.country = GetFlagStr(this.endIpOff + 4);
        this.local = (1 == this.countryFlag) ? " " : this.GetFlagStr(this.endIpOff + 8);
        break;
      default:
        this.country = this.GetFlagStr(this.endIpOff + 4);
        this.local = this.GetFlagStr(objfs.Position);
        break;
    }
    return " ";
  }

  /// <summary>
  /// 获取国家/区域字符串
  /// </summary>
  /// <param name="offSet"></param>
  /// <returns></returns>
  private string GetFlagStr(long offSet)
  {
    int flag = 0;
    byte[] buff = new Byte[3];
    while (1 == 1)
    {
      //objfs.Seek(offSet,SeekOrigin.Begin);
      objfs.Position = offSet;
      flag = objfs.ReadByte();
      if (flag == 1 || flag == 2)
      {
        objfs.Read(buff, 0, 3);
        if (flag == 2)
        {
          this.countryFlag = 2;
          this.endIpOff = offSet - 4;
        }
        offSet = Convert.ToInt64(buff[0].ToString()) + Convert.ToInt64(buff[1].ToString()) * 256 + Convert.ToInt64(buff[2].ToString()) * 256 * 256;
      }
      else
      {
        break;
      }
    }

    if (offSet < 12)
      return " ";

    objfs.Position = offSet;
    return GetStr();
  }


  private string GetStr()
  {
    byte lowC = 0;
    byte upC = 0;
    string str = "";
    byte[] buff = new byte[2];
    while (1 == 1)
    {
      lowC = (Byte)objfs.ReadByte();
      if (lowC == 0)
        break;
      if (lowC > 127)
      {
        upC = (byte)objfs.ReadByte();
        buff[0] = lowC;
        buff[1] = upC;
        System.Text.Encoding enc = System.Text.Encoding.GetEncoding("GB2312");
        str += enc.GetString(buff);
      }
      else
      {
        str += (char)lowC;
      }
    }
    return str;
  }

  /// <summary>
  /// 获取IP地址
  /// </summary>
  /// <returns></returns>
  public string IPLocation()
  {
    this.QQwry();
    return this.country + this.local;
  }

  public string IPLocation(string dataPath, string ip)
  {
    this.dataPath = dataPath;
    this.ip = ip;
    this.QQwry();
    return this.country + this.local;
  }
}

 调用方法：

IPScanner objScan = new IPScanner();
//string ip = Request.ServerVariables.Get("REMOTE_ADDR");//自动获取用户IP
string ip = "8.8.8.8";
objScan.DataPath = Server.MapPath("~/qqwry.dat");
objScan.IP = ip;
string addre = objScan.IPLocation();
Response.Write(objScan.ErrMsg + addre);