Best way to set a strikethrough on individual cells of the WPF DataGrid?

Question

What is the best (easy) way to set the font to a strikethrough style on individual cells of the WPF DataGrid?

...

Options that I'm aware of are inserting TextBlock controls in individual cells or using a DataGridTemplateColumn - and using the TextDecorations property therein. Either way this is quite a mission, I'd like to use the default AutoGenerate Columns function of DataGrid, especially since my ItemsSource is a DataTable.

As and aside, is there any way to access the TextBlock generated using the default DataGridTextColumn?

Answer 1

<DataGridTextColumn Binding="{Binding Name}">
    <DataGridTextColumn.ElementStyle>
        <Style TargetType="{x:Type TextBlock}">
            <Setter Property="TextDecorations" Value="Strikethrough"/>
        </Style>
    </DataGridTextColumn.ElementStyle>
</DataGridTextColumn>

Of course you can wrap the setter in a DataTrigger to use it selectively.

Answer 2

If you want to bind the strikethrough based on a particular cell, you have a binding problem, because the DataGridTextColumn.Binding changes only the content of TextBox.Text. If the value of the Text property is all you need you can bind to the TextBox itself:

<Setter Property="TextDecorations" 
  Value="{Binding RelativeSource={RelativeSource Self}, 
  Path=Text, 
  Converter={StaticResource TextToTextDecorationsConverter}}" />

But if you want to bind to something different than TextBox.Text, you have to bind through the DataGridRow, which is a parent of the TextBox in the visual tree. The DataGridRow has an Item property, which gives access to the complete object used for the whole row.

<Setter Property="TextDecorations" 
  Value="{Binding RelativeSource={RelativeSource AncestorType={x:Type DataGridRow}}, 
  Path =Item.SomeProperty, 
  Converter={StaticResource SomePropertyToTextDecorationsConverter}}" />

The converter looks like this, assuming the something is of type boolean:

public class SomePropertyToTextDecorationsConverter: IValueConverter {
  public object Convert(object value, Type targetType, object parameter, 
    CultureInfo culture) 
  {
      if (value is bool) {
        if ((bool)value) {
          TextDecorationCollection redStrikthroughTextDecoration =
            TextDecorations.Strikethrough.CloneCurrentValue();
          redStrikthroughTextDecoration[0].Pen = 
            new Pen {Brush=Brushes.Red, Thickness = 3 };
          return redStrikthroughTextDecoration; 
        }
      }
      return new TextDecorationCollection(); 
    }

    public object ConvertBack(object value, Type targetType, object parameter, 
      CultureInfo culture) 
    {
      throw new NotImplementedException();
    }
  }