private WaveIn waveSource = null;
private byte[] waveByteArray = null;

private void StartRec() 
{
	if (waveByteArray != null) Array.Clear(waveByteArray, 0, waveByteArray.Length);
	waveSource = new WaveIn();
	waveSource.WaveFormat = new WaveFormat(16000, 1);
	waveSource.DataAvailable += new EventHandler<WaveInEventArgs>(waveSource_DataAvailable);
	waveSource.RecordingStopped += new EventHandler<StoppedEventArgs>(waveSource_RecordingStopped);
	waveSource.StartRecording();
}

void waveSource_DataAvailable(object sender, WaveInEventArgs e)
{
	if (waveByteArray == null)
		waveByteArray = e.Buffer;
	else
		waveByteArray = Combine(waveByteArray, e.Buffer);
}

public byte[] Combine(byte[] a, byte[] b)
{
	byte[] ret = new byte[a.Length + b.Length];
	Buffer.BlockCopy(a, 0, ret, 0, a.Length);
	Buffer.BlockCopy(b, 0, ret, a.Length, b.Length);
	return ret;
}

void waveSource_RecordingStopped(object sender, StoppedEventArgs e)
{
	if (waveSource != null)
	{
		waveSource.Dispose();
		waveSource = null;
	}
}

private void StopRec()
{
	waveSource.StopRecording();
	String r = GoogleSpeechRequest();
}

public string GoogleSpeechRequest()
{
	WebRequest request = WebRequest.Create(gUrl);
	request.Method = "POST";

	byte[] byteArray = waveByteArray;

	// Set the ContentType property of the WebRequest.
	request.ContentType = "audio/l16; rate=16000";
	request.ContentLength = byteArray.Length;

	// Get the request stream.
	Stream dataStream = request.GetRequestStream();
	// Write the data to the request stream.
	dataStream.Write(byteArray, 0, byteArray.Length);

	dataStream.Close();

	// Get the response.
	WebResponse response = request.GetResponse();

	dataStream = response.GetResponseStream();
	// Open the stream using a StreamReader for easy access.
	StreamReader reader = new StreamReader(dataStream);
	// Read the content.
	string responseFromServer = reader.ReadToEnd();

	// Clean up the streams.
	reader.Close();
	dataStream.Close();
	response.Close();

	return responseFromServer;
}