高手请留步，关于delphi 的zlib用法，请指教，着急呀！

Question

我现在想用Delphi 中自带的zlib算法进行一个字符串的压缩与解压缩，但不知怎么用，希望高手能够
提供完整的原代码，我希望是两个函数，一个是压缩函数，传入一个字符串返回一个被压缩的字符
串，一个是解压缩函数，传入一个被压缩过的字符串，返回一个原串，着急呀，不够还可以加分，万
分感激！！！

Answer 1

去网上下载ZLib的完整版吧
有Demo,已经封装好的,比起Dlphi自带那个好用的http://lysoft.7u7.net

Answer 2

对于短字符串压缩做测试没有多少意义，所以建议还是压缩流。
下面是一个压缩OleVariant的，楼主自己去吧，里面是先转成流再压缩，所以楼主可以只看数据流压缩部分
====================================
//压缩
procedure PackStream(var Stream: OleVariant);
var
  ZStream: TCompressionStream;
  InStream:TMemoryStream;
  TempStream:TMemoryStream;
  BStream:TMemoryStream;
  Param:OleVariant;
  p:Pointer;
  pi:Pointer;
  pj:Pointer;
  bSize:int64;
begin
  InStream:=TMemoryStream.Create;
  BStream:=TMemoryStream.Create;
  TempStream:=TMemoryStream.Create;
  pi:=VarArrayLock(Stream);
  try
     TempStream.Write(pi^,VarArrayHighBound(Stream,1)+1);
     ZStream:=TCompressionStream.Create(cldefault, InStream);
     try
        ZStream.CopyFrom(TempStream,0);
     finally
        ZStream.Free;
     end;
     Param:=VarArrayCreate([0,InStream.Size-1+sizeof(bSize)],varByte);
     p:=VarArrayLock(Param);
     try
        pj:=Addr(bSize);
        bSize:=TempStream.Size;
        BStream.Write(pj^,sizeof(bSize));
        BStream.Position:=sizeof(bSize);
        InStream.Position:=0;
        BStream.CopyFrom(InStream,InStream.Size);
        bstream.Position:=0;
        BStream.Read(p^,BStream.Size);
     finally
        VarArrayUnlock(Param);
     end;
  finally
     VarArrayUnlock(Stream);
     InStream.Free;
     TempStream.Free;
     BStream.Free;
  end;
  Stream:=Param;
end;
//-----------------------------------------------
//解压缩
procedure UnPackStream(var Stream: OleVariant);
var
  TempStream:TMemoryStream;
  OutStream:TMemoryStream;
  ZStream: TDecompressionStream;
  BStream:TMemoryStream;
  Param:OleVariant;
  p:Pointer;
  po:Pointer;
  bSize:int64;
  pj:Pointer;
begin
  TempStream:=TMemoryStream.Create;
  BStream:=TMemoryStream.Create;
  OutStream:=TMemoryStream.Create;
  p:=VarArrayLock(Stream);
  try
     TempStream.Write(p^,VarArrayHighBound(Stream,1)+1);
     pj:=Addr(bSize);
     TempStream.Position:=0;
     TempStream.Read(pj^,sizeof(bSize));
     TempStream.Position:=sizeof(bSize);
     if TempStream.Size>0 then BStream.CopyFrom(TempStream,TempStream.Size-sizeof(bSize));
     BStream.Position:=0;
     ZStream:=TDecompressionStream.Create(BStream);
     zstream.Position:=0;
     try
        OutStream.CopyFrom(ZStream,bSize);
        Param:=VarArrayCreate([0,OutStream.Size-1],varByte);
        po:=VarArrayLock(Param);
        try
           OutStream.Position:=0;
           OutStream.Read(po^,OutStream.Size);
        finally
           VarArrayUnlock(Param);
        end;
     finally
        ZStream.Free;
     end;
  finally
     VarArrayUnlock(Stream);
     BStream.Free;
     OutStream.Free;
     TempStream.Free;
  end;
  Stream:=Param;
end;

Answer 3

流都可以，字符串当然行了。
流可以直接调一个文件LoadFromFile，
也可以直接把字符串往里写的SetSize、Write

Answer 4

偶快真要昏了，幸好今天上海的温度还算可以，不那么高，湿度也不错，偶才庆幸挺过来^_^上面使用的是TMemoryStream，偶就用TMemoryStream吧，不过先告诉楼主一声，压缩以后的流并非所有都是可显示字符，中意可能有#0存在，所以返回的数据不能直接使用字符串类，不过可以转换成Base64编码。呵呵，这样子说的话，楼主又会头晕了……汗汗汗procedure TextToStream(const SourceText:String;DestStream:TStream);   
begin
   DestStream.Write(PChar(SourceText)^,Length(SourceText));
end;procedure StreamToText(SourceStream:TStream;var DestText:String);   
begin
   SetLength(DestText,SourceStream.Size);
   SourceStream.Seek(0,0);
   SourceStream.Read(PChar(DestText)^,SourceStream.Size);
end;再昏，这CSDN，咋贴个Base64编码代码都说偶骂人，无语……

Answer 5

下面这段代码是用Base64编码后的Base64编码代码，不知道哪地方又有啥不文明语言，真无语
=====================================================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Answer 6
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还真有一大段发不上来

Answer 7

//对文件进行编码
Procedure EncodeBase64File(FileName:String;
                           DestStream:TStream;
                           ShowMsg:Boolean=true);
var
   SourceStream:TFileStream;
   Buffer:Array[0..BUFFER_SIZE_3] of char; //预读缓冲区
   ssLen:int64;
   DestString:String;
   p:Pointer;
   i:Int64;
   sLen:int64;
   StartTime,EndTime:TDateTime;
begin
   ssLen:=0;
   //打开文件
   SourceStream:=TFileStream.Create(FileName,fmOpenRead or fmShareDenyWrite );
   StartTime:=Now();//开始计时
   try
      i:=0;
      while i<SourceStream.Size do
      begin
         ssLen:=SourceStream.Size-i;  //取文件剩余长度
         if(ssLen>BUFFER_SIZE_3)then  //如果超过预读缓冲取
            ssLen:=BUFFER_SIZE_3;     //则只读取缓冲区大小
         SourceStream.ReadBuffer(Buffer,ssLen);         sLen:=ssLen;
         case (ssLen mod 3) of   //是否为三的倍数，否则添'0'补齐
            2:
               begin
                  Buffer[ssLen+0]:=chr(0);
                  Buffer[ssLen+1]:=chr(0);
                  sLen:=sLen+2;
               end;
            1:
               begin
                  Buffer[ssLen]:=chr(0);
                  Inc(sLen);
               end;
         end;         //编码
         DestString:=EncodeBase64Char( Buffer,sLen);
         sLen:=Length(DestString);
         p:=PChar(DestString);         DestStream.Seek(0,soFromEnd);   //将编码后的数据
         DestStream.WriteBuffer(p^,sLen);//添加到末尾         i:=i+BUFFER_SIZE_3;
      end;      //当数据不足三位时，会使用0补齐，
      //如果将会导致乱码数据的出现，
      //由此在Base64编码当中规定，
      //不足的冲分在编码后需要使用'='字符
      //替换补齐的字符      ssLen:=4;                       //预置替换“补齐”的位置为最后两个
      if DestString[sLen]=chr(10) then//若最后添加的两个是换行回车符
         ssLen:=ssLen+2;              //则把位置往前移两位      case (SourceStream.Size mod 3) of
         1:
            begin
               DestString:='==';
               p:=PChar(DestString);
               DestStream.Seek(2-ssLen,soFromEnd);
               DestStream.WriteBuffer(p^,Length(DestString));
            end;
         2:
            begin
               DestString:='=';
               p:=PChar(DestString);
               DestStream.Seek(3-ssLen,soFromEnd);
               DestStream.WriteBuffer(P^,Length(DestString));
            end;
      end;      EndTime:=Now();          //结束计时      sLen:=SourceStream.Size; //取输入长度
      ssLen:=DestStream.Size;  //取输出长度   finally
      SourceStream.Free();
   end;   //显示编码报告
   if ShowMsg then
      MessageBox(GetActiveWindow(),PChar(
                 'File:'+FileName+chr(13)+chr(10)+
                 'Source File Length:'+IntToStr(sLen)+chr(13)+chr(10)+
                 'Dest Stream Length:'+IntTOStr(ssLen)+chr(13)+chr(10)+
                 'Start At:'+TimeToStr(StartTime)+chr(13)+chr(10)+
                 'Over  At:'+TimeToStr(EndTime)+chr(13)+chr(10)+
                 'Consumed:'+TimeToStr(EndTime-StartTime)),
                 'EncodeBase64 (File to Stream)',
                 MB_OK);
end;