播放声音,等待它完成然后做点什么?

时间:2020-03-06 14:52:26  来源:igfitidea点击:

我正在编写一个Windows Forms应用程序,该应用程序应该播放三个声音文件,并且在每个声音文件的末尾都将更改图像的来源。

我可以使用" System.Media.SoundPlayer"来播放声音。但是,似乎在继续播放声音。

这样做的最终效果是仅播放最后一个声音,并且更改所有图像。

我试过了" Thread.Sleep",但是它使整个GUI进入睡眠状态,并且在进入睡眠状态之后,所有的一切都会立即发生,并且会播放最后一个声音。

更新

我以为PlaySynch在工作,但似乎冻结了我的GUI,这不理想。我还可以做些什么?

解决方案

我们是否尝试过SoundPlayer.PlaySync方法?从帮助中:

The PlaySync method uses the current
  thread to play a .wav file, preventing
  the thread from handling other
  messages until the load is complete.

代替使用Play方法,而使用PlaySync方法。

我们可能想要做的是发出异步声音,然后以不响应用户响应的方式禁用UI。然后,在播放声音后,我们将重新启用UI。这将使我们仍然可以正常绘制UI。

我想出了怎么做。我使用了PlaySynch,但我在绘制线程UI的代码中使用了单独的线程进行播放。播放每个文件后,同一线程还将更新UI。

使用此代码:

[DllImport("WinMM.dll")]
public static extern bool  PlaySound(byte[]wfname, int fuSound);

//  flag values for SoundFlags argument on PlaySound
public static int SND_SYNC        = 0x0000;      // Play synchronously (default).
public static int SND_ASYNC       = 0x0001;      // Play asynchronously.
public static int SND_NODEFAULT   = 0x0002;      // Silence (!default) if sound not found.
public static int SND_MEMORY      = 0x0004;      // PszSound points to a memory file.
public static int SND_LOOP        = 0x0008;      // Loop the sound until next sndPlaySound.
public static int SND_NOSTOP      = 0x0010;      // Don't stop any currently playing sound.
public static int SND_NOWAIT      = 0x00002000;  // Don't wait if the driver is busy.
public static int SND_ALIAS       = 0x00010000;  // Name is a registry alias.
public static int SND_ALIAS_ID    = 0x00110000;  // Alias is a predefined ID.
public static int SND_FILENAME    = 0x00020000;  // Name is file name.
public static int SND_RESOURCE    = 0x00040004;  // Name is resource name or atom.
public static int SND_PURGE       = 0x0040;      // Purge non-static events for task.
public static int SND_APPLICATION = 0x0080;      // Look for application-specific association.
private Thread t; // used for pausing
private string bname;
private int soundFlags;

//-----------------------------------------------------------------
public void Play(string wfname, int SoundFlags)
{
    byte[] bname = new Byte[256];    //Max path length
    bname = System.Text.Encoding.ASCII.GetBytes(wfname);
            this.bname = bname;
            this.soundFlags = SoundFlags;
            t = new Thread(play);
            t.Start();
}
//-----------------------------------------------------------------

private void play()
{
    PlaySound(bname, soundFlags)
}

public void StopPlay()
{
    t.Stop();
}

public void Pause()
{
    t.Suspend(); // Yeah, I know it's obsolete, but it works.
}

public void Resume()
{
    t.Resume(); // Yeah, I know it's obsolete, but it works.
}