如果是这样的话

您可以使用自定义样式来实现:
<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>
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如果通过自动生成列或其他方式在代码隐藏中生成列,则仍可以通过从XAML获取资源来创建分隔符列:
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);
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