用以前放在牛腩公用类库里的IPSearch就行了&＃xff0c;编译没有错误&＃xff0c;不过直接用发现中文乱码&＃xff0c;一通乱改才发现问题&＃xff0c;看最后的ReadString方法 &＃xff0c;
using System;
using System.Collections.Generic;
using System.Text;
using System.IO;
namespace Niunan.WebAssign.Util
{
///
/// 提供从纯真IP数据库搜索IP信息的方法&＃xff1b;
/// 感谢LumaQQ提供纯真IP数据库格式文档&＃xff1b;
/// ----HeDaode 2007-12-28 四川教育学院
///
internal class IPSearch
{
FileStream ipFile;
long ip;
string ipfilePath;
///
/// 构造函数
///
///"ipfilePath">纯真IP数据库路径 public IPSearch(string ipfilePath)
{
this.ipfilePath &＃61; ipfilePath;
}
///
/// 地理位置,包括国家和地区
///
public struct IPLocation
{
public string country, area;
}
///
/// 获取指定IP所在地理位置
///
///
public IPLocation GetIPLocation(string strIP)
{
ip &＃61; IPToLong(strIP);
ipFile &＃61; new FileStream(ipfilePath, FileMode.Open, FileAccess.Read);
long[] ipArray &＃61; BlockToArray(ReadIPBlock());
long offset &＃61; SearchIP(ipArray, 0, ipArray.Length - 1) * 7 &＃43; 4;
ipFile.Position &＃43;&＃61; offset;//跳过起始IP
ipFile.Position &＃61; ReadLongX(3) &＃43; 4;//跳过结束IP
IPLocation loc &＃61; new IPLocation();
int flag &＃61; ipFile.ReadByte();//读取标志
if (flag &＃61;&＃61; 1)//表示国家和地区被转向
{
ipFile.Position &＃61; ReadLongX(3);
flag &＃61; ipFile.ReadByte();//再读标志
}
long countryOffset &＃61; ipFile.Position;
loc.country &＃61; ReadString(flag);
if (flag &＃61;&＃61; 2)
{
ipFile.Position &＃61; countryOffset &＃43; 3;
}
flag &＃61; ipFile.ReadByte();
loc.area &＃61; ReadString(flag);
ipFile.Close();
ipFile &＃61; null;
return loc;
}
///
/// 将字符串形式的IP转换位long
///
///
public long IPToLong(string strIP)
{
byte[] ip_bytes &＃61; new byte[8];
string[] strArr &＃61; strIP.Split(new char[] { &＃39;.&＃39; });
for (int i &＃61; 0; i < 4; i&＃43;&＃43;)
{
ip_bytes[i] &＃61; byte.Parse(strArr[3 - i]);
}
return BitConverter.ToInt64(ip_bytes, 0);
}
///
/// 将索引区字节块中的起始IP转换成Long数组
///
long[] BlockToArray(byte[] ipBlock)
{
long[] ipArray &＃61; new long[ipBlock.Length / 7];
int ipIndex &＃61; 0;
byte[] temp &＃61; new byte[8];
for (int i &＃61; 0; i < ipBlock.Length; i &＃43;&＃61; 7)
{
Array.Copy(ipBlock, i, temp, 0, 4);
ipArray[ipIndex] &＃61; BitConverter.ToInt64(temp, 0);
ipIndex&＃43;&＃43;;
}
return ipArray;
}
///
/// 从IP数组中搜索指定IP并返回其索引
///
///
int SearchIP(long[] ipArray, int start, int end)
{
int middle &＃61; (start &＃43; end) / 2;
if (middle &＃61;&＃61; start)
return middle;
else if (ip < ipArray[middle])
return SearchIP(ipArray, start, middle);
else
return SearchIP(ipArray, middle, end);
}
///
/// 读取IP文件中索引区块
///
///
byte[] ReadIPBlock()
{
long startPosition &＃61; ReadLongX(4);
long endPosition &＃61; ReadLongX(4);
long count &＃61; (endPosition - startPosition) / 7 &＃43; 1;//总记录数
ipFile.Position &＃61; startPosition;
byte[] ipBlock &＃61; new byte[count * 7];
ipFile.Read(ipBlock, 0, ipBlock.Length);
ipFile.Position &＃61; startPosition;
return ipBlock;
}
///
/// 从IP文件中读取指定字节并转换位long
///
///"bytesCount">需要转换的字节数&＃xff0c;主意不要超过8字节 ///
long ReadLongX(int bytesCount)
{
byte[] _bytes &＃61; new byte[8];
ipFile.Read(_bytes, 0, bytesCount);
return BitConverter.ToInt64(_bytes, 0);
}
///
/// 从IP文件中读取字符串
///
///
string ReadString(int flag)
{
if (flag &＃61;&＃61; 1 || flag &＃61;&＃61; 2)//转向标志
ipFile.Position &＃61; ReadLongX(3);
else
ipFile.Position -&＃61; 1;
List<byte> list &＃61; new List<byte>();
byte b &＃61; (byte)ipFile.ReadByte();
while (b > 0)
{
list.Add(b);
b &＃61; (byte)ipFile.ReadByte();
}
return Encoding.GetEncoding("GB2312").GetString(list.ToArray());//.net core下用这个&＃xff0c;要不然会出中文乱码
//return Encoding.Default.GetString(list.ToArray()); //.netframework下用这个
}
}
}
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