c# - UWP 文本到列表框的语音 (c#')

Question

我正在尝试实现文本到语音以按顺序从列表框中读取项目。最初，程序会同时读出所有相互重叠的项目。经过研究，我添加了一个 MediaEnded 处理程序，但我只能设法读出第一个项目，只有在这个实现的情况下。我将不胜感激任何帮助。

    private async void ToSpeechButton_Click(object sender, RoutedEventArgs e)
    {
            MediaElement mediaElement = new MediaElement();
            var tsc = new TaskCompletionSource<bool>();
            mediaElement.MediaEnded += (o, f) => { tsc.TrySetResult(true); };
            mediaElement.Play();

        foreach (var item in ListBox.Items)
        {   
            readText(item.ToString());
            await tsc.Task;
        }                

    }


    private async void readText(string mytext)
    {
        MediaElement mediaplayer = new MediaElement();
        using (var speech = new SpeechSynthesizer())
        {
            speech.Voice = SpeechSynthesizer.AllVoices.First(gender => gender.Gender == VoiceGender.Female);
            SpeechSynthesisStream stream = await speech.SynthesizeTextToStreamAsync(mytext);
            mediaplayer.SetSource(stream, stream.ContentType);
            mediaplayer.Play();
        }
    } 

Answer 1

如果你阅读了 SpeechSynthesizer class 的文档, 你会发现有两种方法可以将文本转换为语音。一个是你用过的，SynthesizeTextToStreamAsync method ，此方法从字符串异步生成语音输出。

另一个是SynthesizeSsmlToStreamAsync method , 此方法从包含 Speech Synthesis Markup Language (SSML) 的字符串异步生成语音输出.

在这种情况下，我们可以使用 SynthesizeSsmlToStreamAsync在每个项目之间暂停语音的方法，例如:

private string allitem;

private void ToSpeechButton_Click(object sender, RoutedEventArgs e)
{
    foreach (var item in listBox.Items)
    {
        var txt = item as ListBoxItem;
        allitem += txt.Content.ToString() + "<break time='500ms'/>";
    }
    readText(allitem);
}

private async void readText(string mytext)
{
    MediaElement mediaplayer = new MediaElement();
    using (var speech = new SpeechSynthesizer())
    {
        speech.Voice = SpeechSynthesizer.AllVoices.First(gender => gender.Gender == VoiceGender.Female);
        string ssml = @"<speak version='1.0' " + "xmlns='http://www.w3.org/2001/10/synthesis' xml:lang='en-US'>" + allitem + "</speak>";
        SpeechSynthesisStream stream = await speech.SynthesizeSsmlToStreamAsync(ssml);
        mediaplayer.SetSource(stream, stream.ContentType);
        mediaplayer.Play();
    }
}

结合这个<break time='500ms'/>每个项目后的字符串，语音将在每个项目后暂停 500 毫秒。