Silverlight 圣诞节下雪效果

       记得原来博客园有人写过下雪的程序，今天正好是平安夜大家看看这个下雪效果如何：

 

 

Blend Behavior代码如下：

public class FallingSNowBehavior : Behavior<Canvas>  {     private static Random randomNumber;       protected override void OnAttached()     {        base.OnAttached();          randomNumber = new Random();          this.Associatedobject.Loaded += new RoutedEventHandler(ApplicationLoaded);     }       void ApplicationLoaded(object sender,RoutedEventArgs e)     {        foreach (FrameworkElement element in this.Associatedobject.Children)        {            FrameworkElement localcopy = element;              double yPosition = Canvas.GetTop(localcopy);            double xPosition = Canvas.GetLeft(localcopy);              double speed = 2 * randomNumber.NextDouble();            double counter = 0;            double radius = 30 * speed * randomNumber.NextDouble();              localcopy.Opacity = 0.2 + randomNumber.NextDouble();              CompositionTarget.Rendering += delegate(object o,EventArgs arg)            {                counter += Math.PI / (180 * speed);                  if (yPosition < Application.Current.RootVisual.DesiredSize.Height)                {                    yPosition += 0.2 + speed;                }                else                {                    yPosition = -localcopy.Height;                }                  Canvas.SetTop(localcopy,yPosition);                Canvas.SetLeft(localcopy,xPosition + radius * Math.Cos(counter));            };        }     }       protected override void OnDetaching()     {        base.OnDetaching();     }  }

源代码下载

 

参考资料

http://www.kirupa.com/blend_silverlight/falling_sNow_silverlight_pg1.htm