1，新建WPF应用程序

2，添加用户控件Message

3，在Message中编写如下代码

<Border x:Name="border" BorderThickness="3" Width="400" Height="60" CornerRadius="30" BorderBrush="Black" Background="#FF293546">
        <TextBlock Height="35" Margin="0,10,20,5"   VerticalAlignment="Top" FontSize="24" FontWeight="Bold" Foreground="#FF507750" Text="看看！我的提示框" Width="197"></TextBlock>
    </Border>

4，在WindowMain的加载事件中编写如下代码

NameScope.SetNameScope(root, new NameScope());
            Message m = new Message();
            m.Name = "aa";

注册名称
            root.RegisterName("aa", m);
            m.SetValue(Canvas.TopProperty,50.0);
            m.SetValue(Canvas.LeftProperty,20.0);
            this.root.Children.Add(m);

//一个改变透明度的故事版

Storyboard sb = new Storyboard();
            DoubleAnimation da = new DoubleAnimation();
            da.To = 0;
            da.Duration = TimeSpan.FromSeconds(5);
            Storyboard.SetTarget(da,m);
            Storyboard.SetTargetProperty(da, new PropertyPath("(UIElement.Opacity)"));
            sb.Children.Add(da);
            sb.Completed += new EventHandler(sb_Completed);
            sb.Begin();
        }

//动画执行完成后移除用户控件
        private void sb_Completed(object sender,EventArgs e)
        {
            this.root.Children.RemoveAt(1);

}