title: How to store FontFamily as a StaticResource?
body: <p>I'm trying to figure out how to set a FontFamily in my App.xaml in such a way that I can declaratively apply that style wherever I need to.
  In the <code>ResourceDictionary</code> I can apply something like:</p>
  
  <pre><code>&lt;System:Double x:Key="SmallTextSize"&gt;10&lt;/System:Double&gt;
  </code></pre>
  
  <p>What I want to do then is something like:</p>
  
  <pre><code>&lt;FontFamily x:Key="MainFont"&gt;Wingdings&lt;/FontFamily&gt;
  </code></pre>
  
  <p>But, the only thing I can get to work is an implicit style, which requires a target, and multiple declarations of the font I want to use.  I need to be able to apply the style I end up with to the FontFamily property of any control.</p>
  
  <p>Here's the closest I can come presently:</p>
  
  <pre><code>&lt;System:String x:Key="MainFont"&gt;Wingdings&lt;/System:String&gt;
  &lt;Style TargetType="UserControl"&gt;
        &lt;Setter Property="FontFamily" Value="{StaticResource MainFont}"&gt;&lt;/Setter&gt;
  &lt;/Style&gt;
  </code></pre>
  
  <p>This implementation doesn't work on something like because it expects MainFont to be  a FontFamily, not a string:</p>
  
  <pre><code>&lt;TextBlock Text="{Binding}" Margin="0,0,0,4" FontWeight="Normal" FontFamily="{StaticResource MainFont}" FontSize="14.667" /&gt;
  </code></pre>
  
  <p>How should I handle this?  Thanks!</p>