Create DataGrid column separator - wpf

Question

Is there a way to create a visual separator between two particular columns in a DataGrid? It doesn't need to be fancy, maybe just a double line or a thicker border.

Answer 1

In case it's something like this
You can achieve using a custom style:
<Window.Resources>
<Style x:Key="DataGridColumnSeparatorStyle" TargetType="DataGridCell">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate>
<Rectangle VerticalAlignment="Stretch" HorizontalAlignment="Stretch" Fill="Gray"/>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</Window.Resources>
<DataGrid x:Name="dataGrid" AutoGenerateColumns="False">
<DataGrid.Columns>
<DataGridTextColumn Header="Start"/>
<DataGridTextColumn Header="End"/>
<!-- Separator column -->
<DataGridTemplateColumn MinWidth="0" Width="2" CellStyle="{StaticResource DataGridColumnSeparatorStyle}"/>
<DataGridTextColumn Header="Start"/>
<DataGridTextColumn Header="End"/>
</DataGrid.Columns>
</DataGrid>
If you generate the columns in code-behind, either by autogenerate columns or other, you can still create the separator column by getting the resource from the XAML:
DataGridTextColumn s1 = new DataGridTextColumn() { Header = "Start" };
DataGridTextColumn s2 = new DataGridTextColumn() { Header = "Start" };
DataGridTextColumn e1 = new DataGridTextColumn() { Header = "End" };
DataGridTextColumn e2 = new DataGridTextColumn() { Header = "End" };
DataGridTemplateColumn column = new DataGridTemplateColumn();
column.MinWidth = 0;
column.Width = 2;
var separatorStyle = (Style)FindResource("DataGridColumnSeparatorStyle");
column.CellStyle = separatorStyle;
dataGrid.Columns.Add(s1);
dataGrid.Columns.Add(e1);
dataGrid.Columns.Add(column);
dataGrid.Columns.Add(s2);
dataGrid.Columns.Add(e2);

Answer 2

I think you have two options. The simplest option will probably be to use a Style and set your DataGrid.CellStyle to the defined style.
<Style x:Key="DataGridBorder" TargetType="DataGridCell">
<Setter Property="BorderBrush" Value="LightGray" />
<Setter Property="BorderThickness" Value="1,1,1,1" />
</Style>
...
<DataGrid CellStyle="{StaticResource DataGridBorder}">
...
The other option is to use a CellTemplate in conjunction with the DataGridTemplateColumn.
<DataGridTemplateColumn>
<DataGridTemplateColumn.CellTemplate>
<DataTemplate>
<Border BorderBrush="LightGray" BorderThickness="1,1,1,1" Margin="-6,-6,-6,-6">
<Grid Margin="6,6,6,6">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*" />
</Grid.ColumnDefinitions>
<TextBlock Text="{Binding Whatever}" Grid.Column="0" TextTrimming="CharacterEllipsis" VerticalAlignment="Center" />
</Grid>
</Border>
</DataTemplate>
</DataGridTemplateColumn.CellTemplate>
</DataGridTemplateColumn>
I haven't tested either of these, and you may have to play with the margins a little bit.

Answer 3

Try this. When navigating through cells using keyboard Tab key, it won't focus the seperator column:
<DataGridTemplateColumn MinWidth="2" MaxWidth="2" IsReadOnly="True" CanUserResize="False">
<DataGridTemplateColumn.HeaderStyle>
<Style TargetType="{x:Type DataGridColumnHeader}">
<Setter Property="Background" Value="Gray" />
<Setter Property="BorderBrush" Value="Gray" />
<Setter Property="BorderThickness" Value="2" />
</Style>
</DataGridTemplateColumn.HeaderStyle>
<DataGridTemplateColumn.CellStyle>
<Style TargetType="{x:Type DataGridCell}">
<Setter Property="BorderBrush" Value="Gray" />
<Setter Property="BorderThickness" Value="2" />
<Setter Property="Focusable" Value="False" />
</Style>
</DataGridTemplateColumn.CellStyle>
</DataGridTemplateColumn>
Source