异步等待直到TTS完成

Question

我试图：

1. 用TTS说些什么
2. 异步等待，直到文本完成
3. 等待一段时间
4. 回到起点

我已经设法做到这一点，但感觉就像一个解决方法，因为我被迫将代码放入synthesizer_SpeakCompleted方法。到目前为止，我的代码如下。我希望有正确方法的任何信息。

public void TestDelay()
{
    DoSomeSpeechAndSignalWhenItsDone();
}

public void DoSomeSpeechAndSignalWhenItsDone()
{
    form.AccessTxtQnReport += "This is written before the speech" + Environment.NewLine;
    synthesizer.SpeakCompleted += new EventHandler<SpeakCompletedEventArgs>(synthesizer_SpeakCompleted);
    synthesizer.SpeakAsync("this is a load of speech and it goes on quite a while");
}

async void  synthesizer_SpeakCompleted(object sender, SpeakCompletedEventArgs e)
{
    //we get here when speech has finished
    form.AccessTxtQnReport += "This is written after the speech" + Environment.NewLine;
    synthesizer.SpeakCompleted -= new EventHandler<SpeakCompletedEventArgs>(synthesizer_SpeakCompleted);

    // Do a delay
    await Task.Delay(3000);
    form.AccessTxtQnReport += "This is written after the delay" + Environment.NewLine;
    // this makes it cycle round for ever
    TestDelay();
}

编辑＆gt;谢谢你的回复。我现在已经将代码更改为这似乎有效，并且看起来更好一些：

// attempt delay using TaskCompletionSource
private TaskCompletionSource<bool> tcs;
public void TestDelay()
{
    tcs = new TaskCompletionSource<bool>();
    DoSomeSpeechAndSignalWhenItsDone();
}

private async void DoSomeSpeechAndSignalWhenItsDone()
{          
    form.AccessTxtQnReport += "This is written before the speech" + Environment.NewLine;
    synthesizer.SpeakCompleted += new EventHandler<SpeakCompletedEventArgs>(synthesizer_SpeakCompleted);
    synthesizer.SpeakAsync("this is a load of speech and it goes on quite a while");
    await tcs.Task;

    form.AccessTxtQnReport += "This is written after the speech" + Environment.NewLine;
    await Task.Delay(2000);
    form.AccessTxtQnReport += "This is written after the delay" + Environment.NewLine;

    // repeat the process ad nauseam
    TestDelay();
}

private  void synthesizer_SpeakCompleted(object sender, SpeakCompletedEventArgs e)
{
    //we get here when speech has finished         
    synthesizer.SpeakCompleted -= new EventHandler<SpeakCompletedEventArgs>(synthesizer_SpeakCompleted);
    //set the task as completed:
    tcs.SetResult(true);          
}