How can I pause an MP3 file using C#?

Question

I have this class I found in a website:

class MP3Handler
{
    private string _command;
    private bool isOpen;
    [DllImport("winmm.dll")]

    private static extern long mciSendString(string strCommand, StringBuilder strReturn, int iReturnLength, IntPtr hwndCallback);

    public void Close()
    {
        _command = "close MediaFile";
        mciSendString(_command, null, 0, IntPtr.Zero);
        isOpen = false;
    }

    public void Open(string sFileName)
    {
        _command = "open \"" + sFileName + "\" type mpegvideo alias MediaFile";
        mciSendString(_command, null, 0, IntPtr.Zero);
        isOpen = true;
    }

    public void Play(bool loop)
    {
        if (isOpen)
        {
            _command = "play MediaFile";
            if (loop)
                _command += " REPEAT";
            mciSendString(_command, null, 0, IntPtr.Zero);
        }
    }
}

Is has the methods for STOP and PLAY. I was wondering if anyone is familiar with the winmm.dll library. How can I pause the song as it's playing and then continue from where it was paused?

Answer 1

Here are all the Multimedia Command Strings.

I see the pause and resume commands are included:

The pause command pauses playing or recording. Most drivers retain the current position and eventually resume playback or recording at this position. CD audio, digital-video, MIDI sequencer, VCR, videodisc, and waveform-audio devices recognize this command.

The resume command continues playing or recording on a device that has been paused using the pause command. Digital-video, VCR, and waveform-audio devices recognize this command. Although CD audio, MIDI sequencer, and videodisc devices also recognize this command, the MCICDA, MCISEQ, and MCIPIONR device drivers do not support it.

So I guess you would have:

bool isPaused = false;

public void Pause() {
    if (isOpen && !isPaused) {
        _command = "pause MediaFile";
        mciSendString(_command, null, 0, IntPtr.Zero);
        isPaused = true;
    }
}

public void Resume() {
    if (isOpen && isPaused) {
        _command = "resume MediaFile";
        mciSendString(_command, null, 0, IntPtr.Zero);
        isPaused = false;
    }
}

Answer 2

This CodeProject article contains a class which handles may of the functions of the winmm.dll library, including pause, and may be helpful for this and in the future.

The basic code, however, is:

    _command = "pause MediaFile";
    mciSendString(_command, null, 0, IntPtr.Zero);