Compress and Decompress using .net framework and built in GZipStream

I recently had a project in which I wanted to compress log files I was transferring between servers. I did not realize till I did some research that the .NET framework has a nice little library built in for creating GZIP files. While I think the maximum recommended size for using this is 4GIG I am well under that.

Here is my Compress / Decompress methods

byte[] startfile = File.ReadAllBytes("e:\\mylog.log");
byte[] comp = null;
byte[] decom = null;




 



comp = CompressBytes(startfile);
Console.WriteLine(comp.Length.ToString());



decom = Decompress(comp);
Console.WriteLine(decom.Length.ToString());

 


private void Compress(byte[] fileBytes)
{
using(MemoryStream ms = new MemoryStream())
{
using(GZipStream gz = new GZipStream(ms,
                                             CompressionMode.Compress,
                                             true))
{
gz.Write(fileBytes, 0, fileBytes.Length);

gz.Close();
}
}
}

private byte[] Decompress(byte[] fileBytes)
{
int buffer_size = 100;

using(MemoryStream ms = new MemoryStream(fileBytes))
{
using(GZipStream gz = new GZipStream(ms,
                                             CompressionMode.Decompress,
                                             true))
{
byte[] bufferFooter = null;
int readOffset = 0;
int totalBytes = 0;
byte[] finalBuffer = null;
int uncompLength = 0;
int compressedFileLength = fileBytes.Length;

// Get last 4 bytes (footer) as they contain the
// original length of the compressed bytes

// byte array to hold footer value
bufferFooter = new byte[4];

// Set position of MemoryStream end of stream
// minus the 4 bytes needed
ms.Position = ms.Length - 4;

// Fill the bufferFooter with the last 4 bytes
ms.Read(bufferFooter, 0, 4);

// Set Stream back to 0
ms.Position = 0;

// Convert footer bytes to the length.
uncompLength = BitConverter.ToInt32(bufferFooter, 0);

// Set a temporary buffer to hold the uncompressed
// information. We also make it slightly larger to
// ensure everything will fit. We will later trim
// off the unused bytes.
finalBuffer = new byte[uncompLength + buffer_size];

while(true)
{
// Read from stream up to buffer size. Note that return
// value is actual bytes read in case the number filled
// is less than we requested.
int bytesRead = gz.Read(finalBuffer,
                                        readOffset,
                                        buffer_size);

// If no bytes returned we are done
if(bytesRead == 0)
{
break;
}

readOffset += bytesRead;
totalBytes += bytesRead;
}

// Trim off unused bytes based
Array.Resize<byte>(ref finalBuffer, totalBytes);

return finalBuffer;
}
}
}

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