How to change cell text color in WPF DataGrid

Here is a way to format DataGrid cell foreground color based on the cell content:

1. Create a value converter:

public class NumericConverter: IValueConverter

{

public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)

{

if (value.ToString() == “”)

return value;

return System.Convert.ToDouble(value) %2 == 0 ? Brushes.Black : Brushes.Red;

}

public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)

{

throw new NotImplementedException();

}

}

2. Define a CellStyle as follows:

<Style x:Key="CurrencyCellStyle"
 TargetType="{x:Type Custom:DataGridCell}">
 <Setter Property="Foreground"
 Value="{Binding RelativeSource={RelativeSource Self}, Path=Content.Text,
Converter={StaticResource NumericConverter}}" />
 </Style>

3. Apply it to the desired DataGridTextColumn:

<Custom:DataGridTextColumn Header="Number" CellStyle="{StaticResource CurrencyCellStyle}" Binding="{Binding Number}"/>