title: XAML Style, Setting Behavior Property on DataTrigger
body: <p>So, I'm new to WPF, so maybe this is trivial but I can't figure it out.</p>
  
  <p>I have a textbox.</p>
  
  <pre><code>&lt;TextBox Text="{Binding NewRateAdjustment.Amount, Mode=TwoWay, NotifyOnValidationError=True, ValidatesOnDataErrors=True,ValidatesOnExceptions=True}" Style="{StaticResource SurchargeAmountTextBox}" AttachedProperties:TextRules.TextRule ="{StaticResource numericRule}"&gt;
      &lt;i:Interaction.Behaviors&gt;
          &lt;gl:NumericTextBoxBehavior DecimalLimit="2" /&gt;
      &lt;/i:Interaction.Behaviors&gt;
  &lt;/TextBox&gt;
  </code></pre>
  
  <p>Now, I need to change the DecimalLimit based upon the choice in a drop down on the page, so I created this Style.</p>
  
  <pre><code>&lt;Style x:Key="SurchargeAmountTextBox" TargetType="{x:Type TextBox}" BasedOn="{StaticResource DefaultTextBox}"&gt;
      &lt;Style.Triggers&gt;
          &lt;DataTrigger Binding="{Binding Path=NewRateAdjustment.SelectedRateAdjustment.CalculationMethod.Name, UpdateSourceTrigger=PropertyChanged}" Value="Fuel"&gt;
              &lt;Setter Property="Background" Value="Red"/&gt;
          &lt;/DataTrigger&gt;
          &lt;DataTrigger Binding="{Binding Path=NewRateAdjustment.SelectedRateAdjustment.CalculationMethod.Name, UpdateSourceTrigger=PropertyChanged}" Value=""&gt;
              &lt;Setter Property="Background" Value="Green"/&gt;
          &lt;/DataTrigger&gt;
      &lt;/Style.Triggers&gt;
  &lt;/Style&gt;
  </code></pre>
  
  <p>It seems to work for the colors.  But how do write the Property Setter for the DecimalLimit???</p>