You after something like: "If (x == 1), make the background of this control blue"? If this is what you need, you can use data triggers. Here is an example that changes the background color of a control based on certain data. In this example, I made it part of the style and used it later in some controls.
<UserControl.Resources>
<Style x:Key="ColoringStyle" TargetType="{x:Type DockPanel}">
<Style.Triggers>
<DataTrigger Binding="{Binding Path=Coloring}" Value="Red">
<Setter Property="Background" Value="#33FF0000"></Setter>
</DataTrigger>
<DataTrigger Binding="{Binding Path=Coloring}" Value="Blue">
<Setter Property="Background" Value="#330000FF"></Setter>
</DataTrigger>
<DataTrigger Binding="{Binding Path=Coloring}" Value="White">
<Setter Property="Background" Value="#33FFFFFF"></Setter>
</DataTrigger>
</Style.Triggers>
</Style>
</UserControl.Resources>
"" "", "" "", DockPanel.
<DockPanel Style="{StaticResource ColoringStyle}">
...
</DockPanel>