WPF DataGrid, Read-Only Row

A common requirement for a DataGrid is to have entire rows that are read-only.  You may have a list of records in your DataGrid and some need to be locked for various reasons.  Unfortunately, in the XAML definition of a DataGrid, there isn’t a way to mark a row as being Read-Only.  To accomplish this without tying my view to my model or rewriting the DataGrid, I’m utilizing the BeginningEdit event, the Tag property of the DataGridRow, and created a style for the DataGridRow with a DataTrigger to put everything together.

First thing I did was to make sure my Model had an IsReadOnly property to latch onto, in the attached sample code, I did this by adding the property to one of the Customer in the Northwind database . 


Next, using a Trigger in my DataGridRow style, if the data item’s IsReadOnly property evaluates to “True” then I set the DataGridRow ‘s Tag to a string I can look for in my BeginningEdit event handler.  In the sample project attached and in the code snippets below, I used the string “ReadOnly”.  For a visual cue, I also set the HeaderTemplate to show an image to indicate that the row is locked. 

XAML Styles
  1. <!– Row Header Template to show a Locked icon.–>
  2. <DataTemplate x:Key="rowHeaderTemplate">
  3.     <StackPanel Orientation="Horizontal">
  4.         <Image x:Name="editImage" Source="Images/lock.gif" Width="16" Margin="1,0" />
  5.     </StackPanel>
  6. </DataTemplate>
  7. <!– DataGridRow Style –>
  8. <Style x:Key="ReadOnlyCheck" TargetType="{x:Type DataGridRow}">
  9.     <Style.Triggers>
  10.         <DataTrigger Binding="{Binding IsReadOnly}" Value="True">
  11.             <Setter Property="Tag" Value="ReadOnly" />
  12.             <Setter Property="HeaderTemplate" Value="{StaticResource rowHeaderTemplate}">
  13.             </Setter>
  14.         </DataTrigger>
  15.     </Style.Triggers>
  16. </Style>



Finally, in my BeginningEdit event handler for my DataGrid, I look at the Row going into Edit Mode, if its Tag property has been set to “ReadOnly” I cancel the event so it never makes it into edit mode.  This enforces the IsReadOnly property from my mode.

BeginningEdit Event Handler
  1. /// <summary>
  2. /// Event Handler for BeginningEdit Event of DataGrid.  If the Row entering into Edit Mode has a Tag set to "ReadOnly",
  3. /// cancel the edit.
  4. /// </summary>
  5. /// <param name="sender">Reference to the DataGrid</param>
  6. /// <param name="e">Instance of DataGridBeginningEditEventArgs</param>
  7. private void dataGrid_BeginningEdit(object sender, DataGridBeginningEditEventArgs e)
  8. {
  9.     if (((DataGridRow)e.Row).Tag != null && ((DataGridRow)e.Row).Tag.ToString() == "ReadOnly")
  10.     {
  11.         e.Cancel = true;
  12.     }
  13. }


Sample Code Download

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