我对使用NAudio有点陌生,所以我肯定缺少一些重要的东西,因此就是这个问题。

从示例/演示代码开始,我整理了一个尽可能简单的类来播放MP3或WAV文件:

public class AudioPlayer : IDisposable
{
    WaveStream _waveStream; // sound data stream
    WaveChannel32 _waveChannel32; // sound channel ??
    IWavePlayer _iWavePlayer; // sound output driver

    public bool IsPlaying
    {
        get { return _iWavePlayer != null
                     && _iWavePlayer.PlaybackState
                         != Wave.PlaybackState.Stopped; }
    }

    public PlaybackState PlaybackState
    {
        get { return _iWavePlayer.PlaybackState; }
    }

    public void LoadMp3(byte[] mp3Bytes)
    {
        Load(CreateInputStreamFromMp3Bytes(mp3Bytes));
    }

    public void LoadFile(string filename)
    {
        Load(CreateInputStream(filename));
    }

    void Load(WaveStream waveStream)
    {
        if (_iWavePlayer != null)
            Dispose();
        _iWavePlayer = new WaveOut();
        _iWavePlayer.PlaybackStopped +=
            new EventHandler(_iWavePlayer_PlaybackStopped);
        _waveStream = waveStream;
        _waveChannel32 = new WaveChannel32(_waveStream);
        _waveChannel32.PadWithZeroes = false;
        _iWavePlayer.Init(_waveChannel32);
    }

    void _iWavePlayer_PlaybackStopped(object sender, EventArgs e)
    {
        Stop();
    }

    static WaveStream CreateInputStreamFromMp3Bytes(byte[] mp3Bytes)
    {
        return new Mp3FileReader(new MemoryStream(mp3Bytes), false);
    }

    static WaveStream CreateInputStream(string fileName)
    {
        if (fileName.EndsWith(".wav"))
            return new WaveFileReader(fileName);
        else if (fileName.EndsWith(".mp3"))
            return new Mp3FileReader(fileName);
        else
            throw new InvalidOperationException("Unsupported extension");
    }

    public void Play()
    {
        _iWavePlayer.Play();
    }

    public void Stop()
    {
        if (_iWavePlayer != null
                && _iWavePlayer.PlaybackState != PlaybackState.Stopped) {
            _iWavePlayer.Stop();
            _waveStream.Position = 0;
        }
    }

    public void Dispose()
    {
        Stop();
        if (_iWavePlayer != null) {
            _iWavePlayer.Dispose();
            _iWavePlayer = null;
        }
        if (_waveChannel32 != null) {
            _waveChannel32.Dispose();
            _waveChannel32 = null;
        }
        if (_waveStream != null) {
            _waveStream.Dispose();
            _waveStream = null;
        }
    }
}

我正在使用有问题的代码播放MP3文件(不是WAV)。

它在大多数情况下都可以正常工作,考虑到我将能够在项目中替换MediaElements,这非常棒。我遇到的问题是,一旦PlaybackStopped触发,PlaybackState会停留在Playing上,而不是更改为Stopped。为了解决这个问题,我订阅了PlaybackStopped并从那里调用Stop()

我必须这样调用Stop()是正常的吗?还是我在这里缺少什么?

最佳答案

看起来像个错误。如果您查看NAudio代码,WaveOut不会更改PlaybackState中的RaisePlaybackStoppedEvent。但是DirectSoundOut会将其更改为已停止。有点疯狂。

08-28 13:15