String sourcefilename = FILETOBECOMPRESSED;
Filestream sourcefile = File.OpenRead(sourcefilename);
Filestream destinationfile = File.Create(outputfilename);
GZipStream compressionstream = new GZipStream(destinationfile, CompressionMode.Compress);
int sourcebyte = sourcefile.ReadByte();
while(sourcebyte != -1)
{
	compressionstream.WriteByte((byte)sourcebyte);
	sourcebyte = sourcefile.ReadByte();
}
//csharp/7605