使用TIdCompressorZLib压缩TIdMemoryBufferStream(compressing TIdMemoryBufferStream with TIdCompressorZLib)

我问的是压缩TIdMemoryBufferStream的可能性使用TIdCompressorZLib如何使用以下代码正确完成

procedure TClientThread.SendBuffer(Buffer: TIdBytes; BufferSize: Cardinal); Var Strm: TIdMemoryBufferStream; IdCompressorZLib : TIdCompressorZLib; begin Strm := TIdMemoryBufferStream.Create(PByte(Buffer), BufferSize); IdCompressorZLib := TIdCompressorZLib.Create(nil); try // then can't figure what the right process to do FTCP.Socket.WriteLn('Stream'); FTCP.Socket.LargeStream := True; FTCP.Socket.Write(Strm, 0, True); finally FreeAndNil(Strm); FreeAndNil(IdCompressorZLib); end; end;

我不确定需要做的正确过程

作为示例我应该创建另一个变量作为StrmB然后调用压缩它？

i am asking about the possibility of compressing TIdMemoryBufferStream Using TIdCompressorZLib how can it be done properly using the following code

i am not sure about the right process that needs to be done

as example should i create another variable as StrmB then calling the compress to it ?

最满意答案

TIdCompressorZLib组件仅用于TIdHTTP和TIdFTP组件的Compressor属性。

对于通过TCP连接进行通用压缩，可以将TIdCompressionIntercept组件分配给TCP连接的IOHandler.Intercept属性，例如：

var Compressor : TIdCompressionIntercept; begin Compressor := TIdCompressionIntercept.Create(nil); try Compressor.CompressionLevel := 9; FTCP.Socket.Intercept := Compressor; try // any data written here will be compressed.... finally FTCP.Socket.Intercept := nil; end; finally Compressor.Free; end; end;

但是，由于您要发送压缩数据的字节大小（通过在TIdIOHandler.Write(TStream)中将AWriteByteCount参数设置为True），因此无法使用压缩截距。

Indy的IdZLib单元有一个TCompressionStream类，以及各种...CompressStream/Ex()函数，你可以使用它们，例如：

procedure TClientThread.SendBuffer(Buffer: TIdBytes; BufferSize: Cardinal); var Strm: TMemoryStream; Compressor : TCompressionStream; begin Strm := TMemoryStream.Create; try Compressor := TCompressionStream.Create(clMax, Strm, False); try WriteTIdBytesToStream(Compressor, Buffer, BufferSize); finally Compressor.Free; end; FTCP.Socket.WriteLn('Stream'); FTCP.Socket.LargeStream := True; FTCP.Socket.Write(Strm, 0, True); finally Strm.Free; end; end;

要么：

procedure TClientThread.SendBuffer(Buffer: TIdBytes; BufferSize: Cardinal); var InStrm: TIdMemoryBufferStream; OutStrm: TMemoryStream; begin OutStrm := TMemoryStream.Create; try InStrm := TIdMemoryBufferStream.Create(PByte(Buffer), BufferSize); try CompressStreamEx(InStrm, OutStrm, clMax, zsZLib); finally InStrm.Free; end; FTCP.Socket.WriteLn('Stream'); FTCP.Socket.LargeStream := True; FTCP.Socket.Write(OutStrm, 0, True); finally OutStrm.Free; end; end;

The TIdCompressorZLib component is intended to be used only with the Compressor property of the TIdHTTP and TIdFTP components.

For general purpose compression over a TCP connection, you can assign a TIdCompressionIntercept component to the TCP connection's IOHandler.Intercept property, eg:

However, since you are sending the byte size of the compressed data (by setting the AWriteByteCount parameter to True in TIdIOHandler.Write(TStream)), that will not work with the compression intercept.

Indy's IdZLib unit has a TCompressionStream class, and various ...CompressStream/Ex() functions, that you can use instead, eg:

Or:

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