<Grid.RowDefinitions>
    <RowDefinition Height="Auto"/>
    <RowDefinition Height="Auto"/>
    <RowDefinition Height="Auto"/>
    <RowDefinition Height="Auto"/>
    <RowDefinition Height="Auto"/>
</Grid.RowDefinitions>

<TextBlock Text="CheckBox Demonstration" Margin="0,20,10,20"
    FontFamily="Verdana" FontSize="18" FontWeight="Bold"
    Foreground="#FF5C9AC9" Grid.Row="0"/>

<!-- two state CheckBox -->
<CheckBox x:Name="cb1" Grid.Row="1" Content="Two State CheckBox" 
          Checked="HandleCheck" Unchecked="HandleUnchecked" Margin="5,0,0,0" />
<TextBlock x:Name="text1" Grid.Row="2" Margin="5,0,0,0" />

<!-- three state CheckBox -->
<CheckBox x:Name="cb2" Grid.Row="3" Content="Three State CheckBox" IsThreeState="True" Checked="HandleCheck" 
    Indeterminate="HandleThirdState" Unchecked="HandleUnchecked" Margin="5,10,0,0" />
<TextBlock x:Name="text2" Grid.Row="4" Margin="5,0,0,0" />


...


<Grid.RowDefinitions>
    <RowDefinition Height="Auto"/>
    <RowDefinition Height="Auto"/>
    <RowDefinition Height="Auto"/>
    <RowDefinition Height="Auto"/>
    <RowDefinition Height="Auto"/>
</Grid.RowDefinitions>

<TextBlock Text="CheckBox Demonstration" Margin="0,20,10,20"
    FontFamily="Verdana" FontSize="18" FontWeight="Bold"
    Foreground="#FF5C9AC9" Grid.Row="0"/>

<!-- two state CheckBox -->
<CheckBox x:Name="cb1" Grid.Row="1" Content="Two State CheckBox" 
          Checked="HandleCheck" Unchecked="HandleUnchecked" Margin="5,0,0,0" />
<TextBlock x:Name="text1" Grid.Row="2" Margin="5,0,0,0" />

<!-- three state CheckBox -->
<CheckBox x:Name="cb2" Grid.Row="3" Content="Three State CheckBox" IsThreeState="True" Checked="HandleCheck" 
    Indeterminate="HandleThirdState" Unchecked="HandleUnchecked" Margin="5,10,0,0" />
<TextBlock x:Name="text2" Grid.Row="4" Margin="5,0,0,0" />

private void HandleCheck(object sender, RoutedEventArgs e)
{
    CheckBox cb = sender as CheckBox;
    if (cb.Name == "cb1")
        text1.Text = "Two state CheckBox checked.";
    else
        text2.Text = "Three state CheckBox checked.";
}

private void HandleUnchecked(object sender, RoutedEventArgs e)
{
    CheckBox cb = sender as CheckBox;
    if (cb.Name == "cb1")
        text1.Text = "Two state CheckBox unchecked.";
    else
        text2.Text = "Three state CheckBox unchecked.";
}

private void HandleThirdState(object sender, RoutedEventArgs e)
{
    CheckBox cb = sender as CheckBox;
    text2.Text = "Three state CheckBox indeterminate.";
}