title: Silverlight DataGrid Header Horizontal Alignment
body: <p>I want to change the alignment of a header on a datagrid in Silverlight, and I can't seem to figure out how to do it. Here's what I have so far:</p>
  
  <pre><code>  &lt;data:DataGridTextColumn Header="#" 
                              IsReadOnly="True"
                              ElementStyle="{StaticResource CenterAlignStyle}" 
                              Binding="{Binding OutlineNumber, Mode=OneWay}" &gt;
      &lt;data:DataGridTextColumn.HeaderStyle&gt;
        &lt;Style TargetType="prim:DataGridColumnHeader"&gt;
          &lt;Setter Property="HorizontalAlignment" Value="Center"/&gt;
        &lt;/Style&gt;
      &lt;/data:DataGridTextColumn.HeaderStyle&gt;
    &lt;/data:DataGridTextColumn&gt;
  </code></pre>
  
  <p>No matter what I try, I can't seem to change the default alignment, which appears to be "left."</p>