纯真IP数据库解析Delphi D10.1下正常使用

直接一个单元，代码分享出来。

 unit   Net.IPLocation;

 interface

 uses System.Classes, System.SysUtils, Winapi.WinSock, Vcl.Forms,
   System.Math, System.SyncObjs;

 type
   TIPLocation = class(TObject)
   private
     QQWryFileName: string;
     QQWryFileStream: TBufferedFileStream;
     QQWryFileSize: Cardinal;
     IPRecordNum: Cardinal;
     FirstIPIndexOffset, LastIPIndexOffset: Cardinal;
     FLock: TCriticalSection;

     function GetQQWryFileName: string;
     function GetQQWryFileSize: Cardinal;
     function GetIPRecordNum: Cardinal;
     function GetQQWryDate: TDate;
     function GetQQWryDataFrom: string;
     function GetIPLocation(IPLocationOffset: Cardinal): TStringlist;
     function GetIPMsg(IPRecordID: Cardinal): TStringlist;
     function GetIPRecordID(IP: string): Cardinal;
     function GetIPValue(IP: string): Cardinal;
   public
     constructor Create(cQQWryFileName: string);
     destructor Destroy; override;
     function GetLocation(IP: string): String;
   end;

 function IPLocation: TIPLocation;

 implementation

 var
   __IPLocation: TIPLocation;

 function IPLocation: TIPLocation;
 begin
   if __IPLocation = nil then
     __IPLocation := TIPLocation.Create(ExtractFilePath(ParamStr()) +
       'qqwry.dat');

   Result := __IPLocation;
 end;

 { TIPLocation }

 constructor TIPLocation.Create(cQQWryFileName: string);
 begin
   inherited Create;
   FLock := TCriticalSection.Create;
   QQWryFileName := cQQWryFileName;
   QQWryFileStream := TBufferedFileStream.Create(QQWryFileName,
     fmOpenRead or fmShareDenyWrite, );
   QQWryFileSize := QQWryFileStream.Size;
   QQWryFileStream.Read(FirstIPIndexOffset, );
   QQWryFileStream.Read(LastIPIndexOffset, );
   IPRecordNum := (LastIPIndexOffset - FirstIPIndexOffset) div  + ;
 end;

 destructor TIPLocation.Destroy;
 begin

   QQWryFileStream.Free;
   FLock.Free;
   inherited Destroy;
 end;

 function TIPLocation.GetIPLocation(IPLocationOffset: Cardinal): TStringlist;
 const
   // 实际信息字串存放位置的重定向模式
   REDIRECT_MODE_ = ;
   REDIRECT_MODE_ = ;
 var
   RedirectMode: byte;
   CountryFirstOffset, CountrySecondOffset: Cardinal;
   CountryMsg, AreaMsg: string;
   //
   function ReadString(StringOffset: Cardinal): ansistring;
   var
     ReadByte: ansichar;
   begin
     Result := '';
     QQWryFileStream.Seek(StringOffset, soFromBeginning);
     QQWryFileStream.Read(ReadByte, );
     while ord(ReadByte) <>  do
     begin
       Result := Result + ReadByte;
       QQWryFileStream.Read(ReadByte, );
     end;
   end;
 //
   function ReadArea(AreaOffset: Cardinal): ansistring;
   var
     ModeByte: byte;
     ReadAreaOffset: Cardinal;
   begin
     ReadAreaOffset := ;
     QQWryFileStream.Seek(AreaOffset, soFromBeginning);
     QQWryFileStream.Read(ModeByte, );
     if (ModeByte = REDIRECT_MODE_) or (ModeByte = REDIRECT_MODE_) then
     begin
       QQWryFileStream.Read(ReadAreaOffset, );
       if ReadAreaOffset =  then
         Result := '未知地区'
       else
         Result := ReadString(ReadAreaOffset);
     end
     else
     begin
       Result := ReadString(AreaOffset);
     end;
   end;

 begin
   CountryFirstOffset := ;
   CountrySecondOffset := ;
   // 跳过4个字节，该4字节内容为该条IP信息里IP地址段中的终止IP值
   QQWryFileStream.Seek(IPLocationOffset + , soFromBeginning);
   // 读取国家信息的重定向模式值
   QQWryFileStream.Read(RedirectMode, );
   // 重定向模式1的处理
   if RedirectMode = REDIRECT_MODE_ then
   begin
     // 模式值为1，则后3个字节的内容为国家信息的重定向偏移值
     QQWryFileStream.ReadData(CountryFirstOffset, );
     // 进行重定向
     QQWryFileStream.Seek(CountryFirstOffset, soFromBeginning);
     // 第二次读取国家信息的重定向模式
     QQWryFileStream.Read(RedirectMode, );
     // 第二次重定向模式为模式2的处理
     if RedirectMode = REDIRECT_MODE_ then
     begin
       // 后3字节的内容即为第二次重定向偏移值
       QQWryFileStream.ReadData(CountrySecondOffset, );
       // 读取第二次重定向偏移值下的字符串值，即为国家信息
       CountryMsg := ReadString(CountrySecondOffset);
       // 若第一次重定向模式为1，进行重定向后读取的第二次重定向模式为2，
       // 则地区信息存放在第一次国家信息偏移值的后面
       QQWryFileStream.Seek(CountryFirstOffset + , soFromBeginning);
       // 第二次重定向模式不是模式2的处理
     end
     else
     begin
       CountryMsg := ReadString(CountryFirstOffset);
     end;
     // 在重定向模式1下读地区信息值
     AreaMsg := ReadArea(QQWryFileStream.Position);
     // 重定向模式2的处理
   end
   else if RedirectMode = REDIRECT_MODE_ then
   begin
     QQWryFileStream.ReadData(CountrySecondOffset, );
     CountryMsg := ReadString(CountrySecondOffset);
     AreaMsg := ReadArea(IPLocationOffset + );
     // 不是重定向模式的处理，存放的即是IP地址信息
   end
   else
   begin
     CountryMsg := ReadString(QQWryFileStream.Position - );
     AreaMsg := ReadArea(QQWryFileStream.Position);
   end;
   Result := TStringlist.Create;
   Result.Add(CountryMsg);
   Result.Add(AreaMsg);
 end;

 function TIPLocation.GetIPMsg(IPRecordID: Cardinal): TStringlist;
 var
   aryStartIP: array [ .. ] of byte;
   strStartIP: string;
   EndIPOffset: Cardinal;
   aryEndIP: array [ .. ] of byte;
   strEndIP: string;
   i: integer;
 begin
   EndIPOffset := ;

   // 根据记录ID号移到该记录号的索引处
   QQWryFileStream.Seek(FirstIPIndexOffset + (IPRecordID - ) * ,
     soFromBeginning);
   // 索引的前4个字节为起始IP地址
   QQWryFileStream.Read(aryStartIP, );
   // 后3个字节是内容区域的偏移值
   // QQWryFileStream.Read(EndIPOffset, 3);
   QQWryFileStream.ReadData(EndIPOffset, );
   // 移至内容区域
   QQWryFileStream.Seek(EndIPOffset, soFromBeginning);
   // 内容区域的前4个字节为终止IP地址
   QQWryFileStream.Read(aryEndIP, );

   // 将起止IP地址转换为点分的形式
   strStartIP := '';
   for i :=  downto  do
   begin
     if i <>  then
       strStartIP := strStartIP + IntToStr(aryStartIP[i]) + '.'
     else
       strStartIP := strStartIP + IntToStr(aryStartIP[i]);
   end;
   strEndIP := '';
   for i :=  downto  do
   begin
     if i <>  then
       strEndIP := strEndIP + IntToStr(aryEndIP[i]) + '.'
     else
       strEndIP := strEndIP + IntToStr(aryEndIP[i]);
   end;
   Result := TStringlist.Create;
   Result.Add(strStartIP);
   Result.Add(strEndIP);
   // 获取该条记录下的IP地址信息
   // 以下三者是统一的：①内容区域的偏移值 ②终止IP地址的存放位置 ③国家信息紧接在终止IP地址存放位置后
   Result.AddStrings(GetIPLocation(EndIPOffset));
 end;

 function TIPLocation.GetIPRecordID(IP: string): Cardinal;
   function SearchIPRecordID(IPRecordFrom, IPRecordTo, IPValue: Cardinal)
     : Cardinal;
   var
     CompareIPValue1, CompareIPValue2: Cardinal;
   begin
     Result := ;
     CompareIPValue1 := ;
     CompareIPValue2 := ;
     QQWryFileStream.Seek(FirstIPIndexOffset + ((IPRecordTo - IPRecordFrom) div
       + IPRecordFrom - ) * , soFromBeginning);
     QQWryFileStream.Read(CompareIPValue1, );
     QQWryFileStream.Seek(FirstIPIndexOffset + ((IPRecordTo - IPRecordFrom) div
       + IPRecordFrom) * , soFromBeginning);
     QQWryFileStream.Read(CompareIPValue2, );
     // 找到了
     if (IPValue >= CompareIPValue1) and (IPValue < CompareIPValue2) then
     begin
       Result := (IPRecordTo - IPRecordFrom) div  + IPRecordFrom;
     end
     else
       // 后半段找
       if IPValue > CompareIPValue1 then
       begin
         Result := SearchIPRecordID((IPRecordTo - IPRecordFrom) div  +
           IPRecordFrom + , IPRecordTo, IPValue);
       end
       else
         // 前半段找
         if IPValue < CompareIPValue1 then
         begin
           Result := SearchIPRecordID(IPRecordFrom, (IPRecordTo - IPRecordFrom)
             div  + IPRecordFrom - , IPValue);
         end;
   end;

 begin
   Result := SearchIPRecordID(, GetIPRecordNum, GetIPValue(IP));
 end;

 function TIPLocation.GetIPRecordNum: Cardinal;
 begin
   Result := IPRecordNum;
 end;

 function TIPLocation.GetIPValue(IP: string): Cardinal;
 var
   tsIP: TStringlist;
   i: integer;
   function SplitStringToStringlist(aString: string; aSplitChar: string)
     : TStringlist;
   begin
     Result := TStringlist.Create;
     while pos(aSplitChar, aString) >  do
     begin
       Result.Add(copy(aString, , pos(aSplitChar, aString) - ));
       aString := copy(aString, pos(aSplitChar, aString) + ,
         length(aString) - pos(aSplitChar, aString));
     end;
     Result.Add(aString);
   end;

 begin
   tsIP := SplitStringToStringlist(IP, '.');
   Result := ;
   for i :=  downto  do
   begin
     Result := Result + StrToInt(tsIP[i]) * trunc(power(,  - i));
   end;
 end;

 function TIPLocation.GetLocation(IP: string): String;
 begin
   FLock.Enter;
   try
     Result := GetIPMsg(GetIPRecordID(IP))[];
   finally
     FLock.Leave;
   end;
 end;

 function TIPLocation.GetQQWryDataFrom: string;
 begin
   Result := GetIPMsg(GetIPRecordNum)[];
 end;

 function TIPLocation.GetQQWryDate: TDate;
 var
   DateString: string;
 begin
   DateString := GetIPMsg(GetIPRecordNum)[];
   DateString := copy(DateString, , pos('IP数据', DateString) - );
   DateString := StringReplace(DateString, '年', '-',
     [rfReplaceAll, rfIgnoreCase]);
   DateString := StringReplace(DateString, '月', '-',
     [rfReplaceAll, rfIgnoreCase]);
   DateString := StringReplace(DateString, '日', '-',
     [rfReplaceAll, rfIgnoreCase]);
   Result := StrToDate(DateString);
 end;

 function TIPLocation.GetQQWryFileName: string;
 begin
   Result := QQWryFileName;
 end;

 function TIPLocation.GetQQWryFileSize: Cardinal;
 begin
   Result := QQWryFileSize;
 end;

 initialization

 finalization

 if __IPLocation <> nil then
   __IPLocation.Free;

 end.