(C#) Decompress Large Binary File in Blocks

Decompresses a large binary file in blocks. This example uses BeginDecompressBytes, MoreDecompressBytes, and EndDecompressBytes.

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// This example requires 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 previously compressed file for decompressing.
// See Compress Large File in Blocks

bool success = facSrc.OpenForRead("qa_data/bmp/compressedBmp.dat");
if (success != true) {
    Debug.WriteLine(facSrc.LastErrorText);
    return;
}

// If we compress in 32K chunks, find out how many blocks there will be.
int blockSize = 32768;
int numBlocks = facSrc.GetNumBlocks(blockSize);

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

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

byte[] decompressedBytes = null;
byte[] compressedBytes = null;

int i = 0;
while (i < numBlocks) {
    compressedBytes = facSrc.ReadBlock(i,blockSize);
    if (i == 0) {
        decompressedBytes = compress.BeginDecompressBytes(compressedBytes);
    }
    else {
        decompressedBytes = compress.MoreDecompressBytes(compressedBytes);
    }

    facDest.FileWrite(decompressedBytes);

    i = i + 1;
}

// At the very end, flush any remaining decompressed bytes, if any.
decompressedBytes = compress.EndDecompressBytes();
facDest.FileWrite(decompressedBytes);

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

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