Deflate Method (flush)

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Ionic Zip Library v1.9.1.6 Deflate Method (flush)

Deflate one batch of data.

Declaration Syntax

Visual Basic

Visual C++

public int Deflate(
	FlushType flush
)

Public Function Deflate ( _
	flush As FlushType _
) As Integer

public:
int Deflate(
	FlushType flush
)

Parameters

flush (FlushType): whether to flush all data as you deflate. Generally you will want to use Z_NO_FLUSH here, in a series of calls to Deflate(), and then call EndDeflate() to flush everything.

Return Value

Z_OK if all goes well.

Remarks

You must have set InputBuffer and OutputBuffer before calling this method.

Examples

CopyC#

private void DeflateBuffer(CompressionLevel level)
{
    int bufferSize = 1024;
    byte[] buffer = new byte[bufferSize];
    ZlibCodec compressor = new ZlibCodec();

    Console.WriteLine("\n============================================");
    Console.WriteLine("Size of Buffer to Deflate: {0} bytes.", UncompressedBytes.Length);
    MemoryStream ms = new MemoryStream();

    int rc = compressor.InitializeDeflate(level);

    compressor.InputBuffer = UncompressedBytes;
    compressor.NextIn = 0;
    compressor.AvailableBytesIn = UncompressedBytes.Length;

    compressor.OutputBuffer = buffer;

    // pass 1: deflate 
    do
    {
        compressor.NextOut = 0;
        compressor.AvailableBytesOut = buffer.Length;
        rc = compressor.Deflate(FlushType.None);

        if (rc != ZlibConstants.Z_OK && rc != ZlibConstants.Z_STREAM_END)
            throw new Exception("deflating: " + compressor.Message);

        ms.Write(compressor.OutputBuffer, 0, buffer.Length - compressor.AvailableBytesOut);
    }
    while (compressor.AvailableBytesIn > 0 || compressor.AvailableBytesOut == 0);

    // pass 2: finish and flush
    do
    {
        compressor.NextOut = 0;
        compressor.AvailableBytesOut = buffer.Length;
        rc = compressor.Deflate(FlushType.Finish);

        if (rc != ZlibConstants.Z_STREAM_END && rc != ZlibConstants.Z_OK)
            throw new Exception("deflating: " + compressor.Message);

        if (buffer.Length - compressor.AvailableBytesOut > 0)
            ms.Write(buffer, 0, buffer.Length - compressor.AvailableBytesOut);
    }
    while (compressor.AvailableBytesIn > 0 || compressor.AvailableBytesOut == 0);

    compressor.EndDeflate();

    ms.Seek(0, SeekOrigin.Begin);
    CompressedBytes = new byte[compressor.TotalBytesOut];
    ms.Read(CompressedBytes, 0, CompressedBytes.Length);
}

Assembly: Ionic.Zip (Module: Ionic.Zip) Version: 1.9.1.8 (1.9.1.8)

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