(C# UWP/WinRT) Compress Large Binary File in Blocks

Compresses a large binary file in blocks. This example uses BeginCompressBytes, MoreCompressBytes, and EndCompressBytes.

Chilkat Universal Windows Platform (UWP) / WinRT Downloads Chilkat for the Universal Windows Platform (UWP)

// This example assumes the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.

Chilkat.FileAccess facSrc = new Chilkat.FileAccess();
Chilkat.FileAccess facDest = new Chilkat.FileAccess();

// Open a large binary file for reading.
bool success = facSrc.OpenForRead("qa_data/bmp/big.bmp");
if (success != true) {
    Debug.WriteLine(facSrc.LastErrorText);
    return;
}

// If we compress in 64K chunks, find out how many blocks there will be.
int blockSize = 65536;
int numBlocks = facSrc.GetNumBlocks(blockSize);

// Open an output file for the compressed data.
success = facDest.OpenForWrite("qa_data/bmp/compressedBmp.dat");
if (success != true) {
    Debug.WriteLine(facDest.LastErrorText);
    return;
}

Chilkat.Compression compress = new Chilkat.Compression();
compress.Algorithm = "deflate";

byte[] fileBytes = null;
byte[] compressedBytes = null;

int i = 0;
while (i < numBlocks) {
    fileBytes = facSrc.ReadBlock(i,blockSize);
    if (i == 0) {
        compressedBytes = await compress.BeginCompressBytesAsync(fileBytes);
    }
    else {
        compressedBytes = await compress.MoreCompressBytesAsync(fileBytes);
    }

    facDest.FileWrite(compressedBytes);

    i = i + 1;
}

// At the very end, flush any remaining compressed bytes, if any.
compressedBytes = await compress.EndCompressBytesAsync();
facDest.FileWrite(compressedBytes);

facSrc.FileClose();
facDest.FileClose();

Debug.WriteLine("Finished compressing file.");