title: How to show row index for wpf toolkit datagrid?
body: <p>I just want to add a index column in wpf toolkit <code>DataGrid</code> to show row index of each data in the <code>DataGrid</code>. How?</p>
  
  <pre><code>&lt;dg:DataGrid ItemsSource="{Binding List}"                              
               SelectionMode="Extended"
               IsReadOnly="True"
               AutoGenerateColumns="False"
               HorizontalAlignment="Left"&gt;
      &lt;dg:DataGrid.Columns&gt;
  
          **&lt;dg:DataGridTextColumn Header="Row Index"&gt;&lt;/dg:DataGridTextColumn&gt;**
          &lt;dg:DataGridTextColumn Header="Branch"
                                 Binding="{Binding Branch.Id}"&gt;&lt;/dg:DataGridTextColumn&gt;
          &lt;dg:DataGridTextColumn Header="Count"
                                 Binding="{Binding RequestCount}"&gt;&lt;/dg:DataGridTextColumn&gt;
      &lt;/dg:DataGrid.Columns&gt;
  &lt;/dg:DataGrid&gt;
  </code></pre>