midi_sequence_playing_real_time

 Below is a simple C# program using NAudio to play a MIDI sequence in real-time using a Windows Forms application. Ensure you have the NAudio NuGet package installed in your project.

Steps to Set Up:

1. Open Visual Studio and create a Windows Forms App (.NET Framework) project.
2. Install the NAudio package via NuGet:

   mathematica
   
   Install-Package NAudio
   

3. Replace the Form1.cs content with the following code.

Code

csharp

using System;
using System.Windows.Forms;
using NAudio.Midi;

namespace MidiPlayerApp
{
    public partial class Form1 : Form
    {
        private MidiOut midiOut;
        private Timer playTimer;
        private int currentNoteIndex = 0;
        private int[] midiNotes = { 60, 62, 64, 65, 67, 69, 71, 72 }; // MIDI notes for C major scale
        private int duration = 500; // Duration for each note in milliseconds

        public Form1()
        {
            InitializeComponent();
            InitializeMidi();
        }

        private void InitializeMidi()
        {
            midiOut = new MidiOut(0); // Initialize MIDI output on the first available device
            playTimer = new Timer
            {
                Interval = duration // Set the timer interval to the duration of each note
            };
            playTimer.Tick += PlayNextNote;
        }

        private void PlayNextNote(object sender, EventArgs e)
        {
            if (currentNoteIndex > 0)
            {
                // Turn off the previous note
                midiOut.Send(MidiMessage.StopNote(midiNotes[currentNoteIndex - 1], 127).RawData);
            }

            if (currentNoteIndex < midiNotes.Length)
            {
                // Play the current note
                midiOut.Send(MidiMessage.StartNote(midiNotes[currentNoteIndex], 127, 1).RawData);
                currentNoteIndex++;
            }
            else
            {
                // Stop the timer and reset the sequence
                playTimer.Stop();
                currentNoteIndex = 0;
            }
        }

        private void PlayButton_Click(object sender, EventArgs e)
        {
            // Start playing the MIDI sequence
            currentNoteIndex = 0;
            playTimer.Start();
        }

        private void StopButton_Click(object sender, EventArgs e)
        {
            // Stop the sequence and turn off any playing notes
            playTimer.Stop();
            if (currentNoteIndex > 0 && currentNoteIndex < midiNotes.Length)
            {
                midiOut.Send(MidiMessage.StopNote(midiNotes[currentNoteIndex - 1], 127).RawData);
            }
            currentNoteIndex = 0;
        }

        private void Form1_FormClosing(object sender, FormClosingEventArgs e)
        {
            // Clean up resources
            midiOut.Dispose();
        }

        private void InitializeComponent()
        {
            this.playButton = new System.Windows.Forms.Button();
            this.stopButton = new System.Windows.Forms.Button();
            this.SuspendLayout();
            // 
            // playButton
            // 
            this.playButton.Location = new System.Drawing.Point(12, 12);
            this.playButton.Name = "playButton";
            this.playButton.Size = new System.Drawing.Size(75, 23);
            this.playButton.TabIndex = 0;
            this.playButton.Text = "Play";
            this.playButton.UseVisualStyleBackColor = true;
            this.playButton.Click += new System.EventHandler(this.PlayButton_Click);
            // 
            // stopButton
            // 
            this.stopButton.Location = new System.Drawing.Point(93, 12);
            this.stopButton.Name = "stopButton";
            this.stopButton.Size = new System.Drawing.Size(75, 23);
            this.stopButton.TabIndex = 1;
            this.stopButton.Text = "Stop";
            this.stopButton.UseVisualStyleBackColor = true;
            this.stopButton.Click += new System.EventHandler(this.StopButton_Click);
            // 
            // Form1
            // 
            this.ClientSize = new System.Drawing.Size(184, 61);
            this.Controls.Add(this.stopButton);
            this.Controls.Add(this.playButton);
            this.Name = "Form1";
            this.Text = "MIDI Player";
            this.FormClosing += new System.Windows.Forms.FormClosingEventHandler(this.Form1_FormClosing);
            this.ResumeLayout(false);
        }

        private Button playButton;
        private Button stopButton;
    }
}

Explanation:

• MidiOut: Used to send MIDI messages to a selected output device.
• Timer: Plays each note at regular intervals (500ms per note in this case).
• Buttons:
  • "Play" starts the sequence.
  • "Stop" stops the sequence and turns off the notes.
• Cleanup: Disposes of the MidiOut object when the form closes.

Running the Application:

1. Run the program.
2. Click "Play" to start playing a sequence of notes (C major scale).
3. Click "Stop" to halt playback.

You can expand the program to load different sequences or change the instrument by sending corresponding MIDI Control Change messages.