CopyStreams

        public static void CopyStreams(Stream sourceStream,Stream destStream) {
            if(sourceStream == null)
                throw new ArgumentNullException("sourceStream");
            if(destStream == null)
                throw new ArgumentNullException("destStream");

            byte[] buffer = new byte[4096];
            for(int len;(len = sourceStream.Read(buffer,0,buffer.Length)) > 0;)
                destStream.Write(buffer,0,len);
        }