MidiPlayer for Unity (using winmm.dll)

MidiPlayer.cs

// Midi Player - unitycoder.com
// MidiOutCaps struct from http://svn.tapr.org/repos_sdr_windows/PowerSDR/trunk/Source/Console/midi.cs
// Midi code from http://www.codeguru.com/columns/dotnet/making-music-with-midi-and-c.html

// USAGE: set proper path+filename inside PlayMidi(), attach this scrip to gameobject in scene and hit play!
// Get midi files from internets, like: http://www.vgmusic.com/music/computer/commodore/commodore/

using UnityEngine;
using System.Runtime.InteropServices;
using System.Text;

public class MidiPlayer : MonoBehaviour
{
    static string res;
    public const int MAXPNAMELEN = 32;
    public struct MidiOutCaps
    {
        public short wMid;
        public short wPid;
        public int vDriverVersion;
        [MarshalAs(UnmanagedType.ByValTStr, SizeConst = MAXPNAMELEN)]
        public string szPname;
        public short wTechnology;
        public short wVoices;
        public short wNotes;
        public short wChannelMask;
        public int dwSupport;
    }

    // MCI INterface
    [DllImport("winmm.dll")]
    private static extern long mciSendString(string command, StringBuilder returnValue, int returnLength, System.IntPtr winHandle);

    // Midi API
    [DllImport("winmm.dll")]
    private static extern int midiOutGetNumDevs();


    [DllImport("winmm.dll")]
    private static extern int midiOutGetDevCaps(System.Int32 uDeviceID, ref MidiOutCaps lpMidiOutCaps, System.UInt32 cbMidiOutCaps);


    [DllImport("winmm.dll")]
    private static extern int midiOutOpen(ref int handle, int deviceID, MidiCallBack proc, int instance, int flags);

    [DllImport("winmm.dll")]
    private static extern int midiOutShortMsg(int handle, int message);

    [DllImport("winmm.dll")]
    private static extern int midiOutClose(int handle);

    private delegate void MidiCallBack(int handle, int msg, int instance, int param1, int param2);

    static string Mci(string command)
    {
        StringBuilder reply = new StringBuilder(256);
        mciSendString(command, reply, 256, System.IntPtr.Zero);
        return reply.ToString();
    }

    void Start()
    {
        var numDevs = midiOutGetNumDevs();
        MidiOutCaps myCaps = new MidiOutCaps();
        var res = midiOutGetDevCaps(0, ref myCaps, (System.UInt32)Marshal.SizeOf(myCaps));

        PlayMidi();
    }

    static void PlayMidi()
    {
        res = System.String.Empty;

        // set path to midi file here
        string filename = Application.dataPath + "/Mids/" + "commando.mid";
        Debug.Log("Loading midi:" + filename);

        res = Mci("open \"" + filename + "\" alias music");
        res = Mci("play music");
    }

    void OnDestroy()
    {
        res = Mci("close music");
    }

    void OnDisable()
    {
        res = Mci("close music");
    }

}