ControlTemplates
(:source lang=XML :)
<Window x:Class="WpfApplication1.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">
<Window.Resources>
<Style TargetType="Button" x:Key="EllipseButton">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="Button">
<Grid>
<Ellipse Fill="{TemplateBinding Background}" Stroke="Black"/>
<ContentPresenter HorizontalAlignment="Center"
VerticalAlignment="Center" />
</Grid>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</Window.Resources>
<Grid>
<Button Height="23" HorizontalAlignment="Left" Margin="34,47,0,0" Name="button1" VerticalAlignment="Top" Width="75">Button</Button>
<Button Style="{StaticResource EllipseButton}" Margin="34,76,0,0" Name="button2" Height="23" HorizontalAlignment="Left" VerticalAlignment="Top" Width="75">Button</Button>
</Grid>
</Window>
