在单个按钮上协调多个IOobservable

Question

我有一个在播放/暂停之间交替的按钮。我想看看是否有一个使用反应式扩展的好解决方案，而不是对布尔值进行翻转。这是对我想法的粗略估计。

var whenPlayClicked = Observable.FromEventPattern<EventArgs>(_playPauseButton, "Click")
    .Take(1)
    .Skip(1)
    .Repeat();
var whenPauseclicked = Observable.FromEventPattern<EventArgs>(_playPauseButton, "Click")
    .Skip(1)
    .Take(1)
    .Repeat();

Answer 1

Rx不提供任何本地运算符来简单地切换布尔值；但是，您可以编写一个非常优雅的Scan查询来避免闭包。

void UserControl_Loaded(object sender, RoutedEventArgs e)
{
  Observable.FromEventPattern(_playPauseButton, "Click")
            .Scan(false, (play, _) => !play)
            .Subscribe(play => { if (play) Play(); else Pause(); });
}
private void Play()
{
  _playPauseButton.Content = "Pause";
}
private void Pause()
{
  _playPauseButton.Content = "Play";
}