Exemplos de WPF 3.5 (Windows Presentation Foundation) - 001 - Hello World

<Window x:Class="_001_HelloWorld.Window1"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Title="Window1" Height="300" Width="300">

    <Grid>
        <Label Height="28" Name="label1" Margin="20" 
               VerticalAlignment="Top" HorizontalAlignment="Center">
               Hello World!!!
        </Label>
        <Button Height="23" Name="button1" VerticalAlignment="Center" 
                HorizontalAlignment="Center" Width="75" 
                Click="button1_Click">Clique aqui</Button>
    </Grid>
</Window>

using System.Windows;
using System.Windows.Media;


namespace _001_HelloWorld
{
    public partial class Window1 : Window
    {
        public Window1()
        {
            InitializeComponent();
        }


        private void button1_Click(object sender, RoutedEventArgs e)
        {
            /*

             * Rendering Tier 0. 
               The video card will not provide any hardware acceleration.
               This corresponds to a DirectX version level of less than 7.0.


             * Rendering Tier 1. 
               The video card can provide partial hardware acceleration.
               This corresponds to a DirectX version >= 7.0 and < 9.0.


             * Rendering Tier 2. 
               All features that can be hardware accelerated will be.
               This corresponds to a DirectX version >= 9.0.

             */

            MessageBox.Show((RenderCapability.Tier >> 16).ToString());
        }
    }
}