WPF故事板死亡

C#:

public partial class MainWindow : Window
{
    Storyboard a = new Storyboard();
    int i;
    public MainWindow()
    {
        InitializeComponent();
        a.Completed += new EventHandler(a_Completed);
        a.Duration = TimeSpan.FromMilliseconds(10);
        a.Begin();
    }

    void a_Completed(object sender, EventArgs e)
    {
        textblock.Text = (++i).ToString();
        a.Begin();
    }
}

XAML:

<Window x:Class="Gui.MainWindow" x:Name="control"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="MainWindow" Height="300" Width="300">
<Canvas>
    <TextBlock Name="textblock"></TextBlock>
</Canvas>

这段代码有什么问题？ 故事板在 20-50 轮后停止。每次都有不同的数字

我相信这是因为在您的代码中，故事板的动画时钟和 TextBlock 的 Text DependencyProperty 之间没有创建任何关系。如果我不得不猜测，我会说故事板何时出现问题，这是由于污染了 DependencyProperty（TextBlock.Text 是 DependencyProperty）更新管道而在某种程度上随机发生的。创建如下所示的关联（RunTimeline 或 RunStoryboard 都可以，但显示查看此内容的替代方法）：

public partial class Window1 : Window
{
    Storyboard a = new Storyboard();
    StringAnimationUsingKeyFrames timeline = new StringAnimationUsingKeyFrames();
    DiscreteStringKeyFrame keyframe = new DiscreteStringKeyFrame();

    int i;

    public Window1()
    {
        InitializeComponent();

        //RunTimeline();
        RunStoryboard();
    }

    private void RunTimeline()
    {
        timeline.SetValue(Storyboard.TargetPropertyProperty, new PropertyPath("(TextBlock.Text)"));
        timeline.Completed += timeline_Completed;
        timeline.Duration = new Duration(TimeSpan.FromMilliseconds(10));
        textblock.BeginAnimation(TextBlock.TextProperty, timeline);
    }

    private void RunStoryboard()
    {
        timeline.SetValue(Storyboard.TargetPropertyProperty, new PropertyPath("(TextBlock.Text)"));
        a.Children.Add(timeline);
        a.Completed += a_Completed;
        a.Duration = new Duration(TimeSpan.FromMilliseconds(10));
        a.Begin(textblock);
    }

    void timeline_Completed(object sender, EventArgs e)
    {
        textblock.Text = (++i).ToString();
        textblock.BeginAnimation(TextBlock.TextProperty, timeline);
    }

    void a_Completed(object sender, EventArgs e)
    {
        textblock.Text = (++i).ToString();
        a.Begin(textblock);
    }
}

只要我愿意让它运行，这对我来说就有效（比其他情况下解决问题所需的时间长约 10 倍）。

Tim