SlimDX的DirectSound模块

网上SlimDX的资源很少，搜到了http://www.xukailun.me/article/238/这篇关于《SlimDX的DirectSound模块应用实战》的文章，备份下来以备不时之需。

1.基本的播放功能

void CreateDirectSound(Guid deviceId, IntPtr handle)
{
    // 音频设备的Id
    _ds = new DirectSound(deviceId);
　　// 需要使用窗口的句柄
    _ds.SetCooperativeLevel(handle, CooperativeLevel.Normal);
}
void Play(string file)
 {
    SecondarySoundBuffer snd = null;
    // 读取wav音频文件
    using (WaveStream ws = new WaveStream(file))
     {
        var desc = new SoundBufferDescription();
            desc.Format = ws.Format;
        desc.Flags = BufferFlags.GlobalFocus | BufferFlags.ControlVolume | BufferFlags.ControlPositionNotify | BufferFlags.GetCurrentPosition2;
            desc.SizeInBytes = (int)ws.Length;
        // 为声音建立二级缓冲区
        snd = new SecondarySoundBuffer(_ds, desc);
        snd.Volume = -200;
        byte[] buffer = new byte[desc.SizeInBytes];
        ws.Read(buffer, 0, buffer.Length);
        snd.Write<byte>(buffer, 0, LockFlags.None);
    }
    snd.Play(0, PlayFlags.None);
} 

2.播放中的回调

AutoResetEvent功能就类似于Java的wait/notify。调用WaitOne方法相当于wait，使当前线程等待；调用Set方法相当于调用notify，通知线程继续执行。

class SoundUnit
{
    public int Id { get; private set; }
    public SoundBuffer Buffer { get; private set; }
    public AutoResetEvent Event { get; private set; }
    public SoundUnit(SoundBuffer buffer)
    {
            this.Id = ++i;
            this.Buffer = buffer;
            this.Event = new AutoResetEvent(false);
    }
}
    void Play(string file)
    {
        SecondarySoundBuffer snd = null;
        SoundUnit su = null;
        // 读取wav音频文件
        using (WaveStream ws = new WaveStream(file))
        {
            var desc = new SoundBufferDescription();
            desc.Format = ws.Format;
            desc.Flags = BufferFlags.GlobalFocus | BufferFlags.ControlVolume |             BufferFlags.ControlPositionNotify | BufferFlags.GetCurrentPosition2;
            desc.SizeInBytes = (int)ws.Length;
            // 为声音建立二级缓冲区
            snd = new SecondarySoundBuffer(_ds, desc);
            snd.Volume = -200;
            byte[] buffer = new byte[desc.SizeInBytes];
            ws.Read(buffer, 0, buffer.Length);
            snd.Write<byte>(buffer, 0, LockFlags.None);
            su = new SoundUnit(snd);
            snd.SetNotificationPositions(new[]{
            // 设置播放结束后回调
            new NotificationPosition{ Event = su.Event, Offset = DSBPN_OFFSETSTOP }         });
        }
        snd.Play(0, PlayFlags.None);
        Console.WriteLine("播放开始：" + su.Id);
        WaitForNotification(su);
    }
    void WaitForNotification(SoundUnit unit)
    {
        new Thread(() =>{
        // 等待播放完成
        unit.Event.WaitOne();
         Console.WriteLine("播放结束：" + unit.Id);     }).Start();
    }