System.IO.Compression.DeflateStream.FlushAsyncCore C# (CSharp) Method

        private async Task FlushAsyncCore(CancellationToken cancellationToken)
        {
            AsyncOperationStarting();
            try
            {
                // Compress any bytes left:
                await WriteDeflaterOutputAsync(cancellationToken).ConfigureAwait(false);

                // Pull out any bytes left inside deflater:
                bool flushSuccessful;
                do
                {
                    int compressedBytes;
                    flushSuccessful = _deflater.Flush(_buffer, out compressedBytes);
                    if (flushSuccessful)
                    {
                        await _stream.WriteAsync(_buffer, 0, compressedBytes, cancellationToken).ConfigureAwait(false);
                    }
                    Debug.Assert(flushSuccessful == (compressedBytes > 0));
                } while (flushSuccessful);
            }
            finally
            {
                AsyncOperationCompleting();
            }
        }