Set CornerRadius on button template

Question

I want to have a Button that defines no CornerRadius and two others that do, how can I achieve this?

<Style TargetType="Button" x:Key="TabButton">
    <Setter Property="Background" Value="White" />
    <Setter Property="TextBlock.TextAlignment" Value="Center" />
    <Setter Property="Template">
        <Setter.Value>
            <ControlTemplate TargetType="Button">
                <Border CornerRadius="0" Background="White" BorderBrush="#ccc" BorderThickness="0,1,1,0" >
                    <ContentPresenter x:Name="contentPresenter" ContentTemplate="{TemplateBinding ContentTemplate}" Content="{TemplateBinding Content}" HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}" Margin="{TemplateBinding Padding}" VerticalAlignment="{TemplateBinding VerticalContentAlignment}"/>
                </Border>
            </ControlTemplate>
        </Setter.Value>
    </Setter>
</Style>

<Style TargetType="Button" x:Key="TabButtonFirst" BasedOn="{StaticResource TabButton}">
    <Setter Property="CornerRadius" Value="3,0,0,0" />
</Style>

<Style TargetType="Button" x:Key="TabButtonLast" BasedOn="{StaticResource TabButton}">
    <Setter Property="CornerRadius" Value="0,0,0,3" />
</Style>

Answer 1

You're not limited to the dependency properties of the control you're templating. In this case, while Button does not have a CornerRadius property, Border does, so you can use Border.CornerRadius instead:

<Style TargetType="Button" x:Key="TabButton">
    <Setter Property="Background" Value="White" />
    <Setter Property="TextBlock.TextAlignment" Value="Center" />
    <Setter Property="Template">
        <Setter.Value>
            <ControlTemplate TargetType="Button">
                <Border CornerRadius="{TemplateBinding Border.CornerRadius}" 
                        Background="White" BorderBrush="#ccc" 
                        BorderThickness="0,1,1,0" >
                    <ContentPresenter x:Name="contentPresenter" 
                                      ContentTemplate="{TemplateBinding ContentTemplate}" 
                                      Content="{TemplateBinding Content}" 
                                      HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}"
                                      Margin="{TemplateBinding Padding}" 
                                      VerticalAlignment="{TemplateBinding VerticalContentAlignment}"/>
                </Border>
            </ControlTemplate>
        </Setter.Value>
    </Setter>
</Style>

<Style TargetType="Button" x:Key="TabButtonFirst" BasedOn="{StaticResource TabButton}">
    <Setter Property="Border.CornerRadius" Value="3,0,0,0" />
</Style>

<Style TargetType="Button" x:Key="TabButtonLast" BasedOn="{StaticResource TabButton}">
    <Setter Property="Border.CornerRadius" Value="0,0,0,3" />
</Style>

With this approach, you no longer need to maintain multiple copies of your control template.