WPF Datagrid Multiple Selection without CTRL or Space

Question

The WPF Datagrid has two selection modes, Single or Extended. The WPF ListView has a third - Multiple. This mode allows you to click and select multiple rows without CTRL or

Answer 1

You can try this simple workaround without having to modifying/inheriting DataGrid control by handling preview mouse down event as follows:

TheDataGrid.PreviewMouseLeftButtonDown += 
                 new MouseButtonEventHandler(TheDataGrid_PreviewMouseLeftButtonDown);


void TheDataGrid_PreviewMouseLeftButtonDown(object sender, MouseButtonEventArgs e)
{
    // get the DataGridRow at the clicked point
    var o = TryFindFromPoint(TheDataGrid, e.GetPosition(TheDataGrid));
    // only handle this when Ctrl or Shift not pressed 
    ModifierKeys mods = Keyboard.PrimaryDevice.Modifiers;
    if (o != null && ((int)(mods & ModifierKeys.Control) == 0 &&
                                                (int)(mods & ModifierKeys.Shift) == 0))
    {
        o.IsSelected = !o.IsSelected;
        e.Handled = true;
    }
}

public static T TryFindFromPoint(UIElement reference, Point point)
                where T:DependencyObject
{
    DependencyObject element = reference.InputHitTest(point) as DependencyObject;
    if (element == null) 
        return null;
    else if (element is T) 
        return (T)element;
    else return TryFindParent(element);
}

The TryFindFromPoint method, from a blog post by Philipp Sumi, is used to get the DataGridRow instance from point you clicked.

By checking ModifierKeys, you can still keep Ctrl and Shift as default behavior.

Only one draw back from this method is that you can't click and drag to perform range select like it can originally.