Font Size Resources
<UserControl x:Class='SilverlightApplication3.MainPage' xmlns='http://schemas.microsoft.com/winfx/2006/xaml/presentation' xmlns:x='http://schemas.microsoft.com/winfx/2006/xaml' xmlns:d='http://schemas.microsoft.com/expression/blend/2008' xmlns:mc='http://schemas.openxmlformats.org/markup-compatibility/2006' mc:Ignorable='d' d:DesignWidth='640' d:DesignHeight='480'> <StackPanel xmlns:s="clr-namespace:System;assembly=mscorlib"> <StackPanel.Resources> <s:Double x:Key="fontsizeLarge">18</s:Double> <s:Double x:Key="fontsizeSmall">14</s:Double> </StackPanel.Resources> <Button HorizontalAlignment="Center" VerticalAlignment="Center" Margin="24"> <Button.FontSize> <StaticResource ResourceKey="fontsizeLarge" /> </Button.FontSize> Button with large FontSize </Button> <Button HorizontalAlignment="Center" VerticalAlignment="Center" Margin="24" FontSize="{StaticResource fontsizeSmall}" > Button with small FontSize </Button> </StackPanel> </UserControl>