Real-Time Audio Data to Byte-Array

Question

With the codes below, the byte array is created as soon as the audio record wav file is saved.

But I need to create this byte-array real-time, for live streams.

How can I do this?

        [DllImport("winmm.dll")]
        private static extern long mciSendString(string command, StringBuilder retstrign, int Returnlength, IntPtr callback);
        public Form1()
        {
            InitializeComponent();
            mciSendString("open new Type waveaudio alias recsound", null, 0, IntPtr.Zero);
            button1.Click += new EventHandler(this.startbutton_Click);

        }

        private void startbutton_Click(object sender, EventArgs e)
        {
            //    throw new NotImplementedException();
            mciSendString("record recsound", null, 0, IntPtr.Zero);
            button2.Click += new EventHandler(this.stopbutton_Click);

        }

        private void stopbutton_Click(object sender, EventArgs e)
        {
            string filename = @"C:\Users\seymk\source\repos\AudioFromSoundCard\test.wav";
            //throw new NotImplementedException();
            mciSendString(@"save recsound C:\Users\seymk\source\repos\AudioFromSoundCard\test.wav", null, 0, IntPtr.Zero);
            mciSendString("close recsound", null, 0, IntPtr.Zero);

            //ReadWav(filename, out float[] L, out float[] R);

            using (WaveFileReader reader = new WaveFileReader(filename))
            {
                Assert.AreEqual(8, reader.WaveFormat.BitsPerSample, "");
                byte[] buffer = new byte[reader.Length];
                int read = reader.Read(buffer, 0, buffer.Length);
                short[] sampleBuffer = new short[read / 2];
                Buffer.BlockCopy(buffer, 0, sampleBuffer, 0, read);

                string text = "Some metadata........" + Environment.NewLine +
 String.Join(" ", buffer.Select(x => x.ToString("x2"))); // <- encoding 

                File.WriteAllText(@"C:\Users\seymk\source\repos\AudioFromSoundCard\Foo.txt", text);
            }
        }