绑定 DoubleAnimation 值时出错

Error when Binding DoubleAnimation values

我正在尝试将我的 DoubleAnimation 属性绑定到代码隐藏中的 c# 变量。

这是我的 XAML:

<Window.Triggers>
    <EventTrigger RoutedEvent="Window.Loaded" >
        <EventTrigger.Actions>
            <BeginStoryboard>
                <Storyboard TargetProperty="Left "  Name ="PlayAnimation">
                    <DoubleAnimation  From="{Binding StartAmount}" To="{Binding EndAmount}" Duration="0:0:0.050"
                                 AutoReverse="True" RepeatBehavior="Forever"
                                 FillBehavior="Stop"/>
                </Storyboard>
            </BeginStoryboard>
        </EventTrigger.Actions>
    </EventTrigger>
</Window.Triggers>

在主窗口中

public MainWindow()
{         
    InitializeComponent();     
    int StartAmount = 50;
    int EndAmount = 100;      
}

启动程序后我得到异常

Cannot animate the 'Left' property on a 'WpfApplication4.MainWindow' using a 'System.Windows.Media.Animation.DoubleAnimation'. For details see the inner exception.

有谁知道它为什么抛出这个异常?

用两个 属性 创建一个 class 像这样:

public class MyClass
{
    public int StartAmount { get; set; }
    public int EndAmount  { get; set; }
}

然后:

public MainWindow()
{
     InitializeComponent();
     MyClass ms = new MyClass { StartAmount = 50, EndAmount = 100 };
     this.DataContext = ms;
}