Animation in Windows 8 apps

在Windows 8 App里边的动画和在silverlight里边还有稍微的区别， 如代码：

using Windows.UI.Xaml;
using Windows.UI.Xaml.Media;
using Windows.UI.Xaml.Media.Animation;
using Windows.UI.Xaml.Controls;

        protected void DemoAnimation()
        {
            Duration m_Dur = new Duration(TimeSpan.FromSeconds(4));
            Storyboard sb = new Storyboard();
            sb.Duration = m_Dur;

            DoubleAnimation topAnimation = new DoubleAnimation();
            topAnimation.Duration = m_Dur;
            DoubleAnimation leftAnimation = new DoubleAnimation();
            leftAnimation.Duration = m_Dur;

            Storyboard.SetTarget(topAnimation, myPictureCanvas);
            Storyboard.SetTargetProperty(topAnimation, "(Canvas.Top)");
            Storyboard.SetTarget(leftAnimation, myPictureCanvas);
            Storyboard.SetTargetProperty(leftAnimation, "(Canvas.Left)");
            topAnimation.EnableDependentAnimation = true;
            leftAnimation.EnableDependentAnimation = true;
            topAnimation.From = 0;
            leftAnimation.From = 0;
            topAnimation.To = 500;
            leftAnimation.To = 500;


            DoubleAnimation heightAnimation = new DoubleAnimation();
            heightAnimation.Duration = m_Dur;
            DoubleAnimation widthAnimation = new DoubleAnimation();
            widthAnimation.Duration = m_Dur;

            Storyboard.SetTarget(heightAnimation, myPictureCanvas);
            Storyboard.SetTargetProperty(heightAnimation, "(Canvas.Height)");
            Storyboard.SetTarget(widthAnimation, myPictureCanvas);
            Storyboard.SetTargetProperty(widthAnimation, "(Canvas.Width)");
            heightAnimation.EnableDependentAnimation = true;
            widthAnimation.EnableDependentAnimation = true;
            heightAnimation.From = 50;
            widthAnimation.From = 50;
            heightAnimation.To = 500;
            widthAnimation.To = 500;
            sb.Children.Add(heightAnimation);
            sb.Children.Add(widthAnimation);

            sb.Children.Add(topAnimation);
            sb.Children.Add(leftAnimation);
            sb.Begin();
        }