Groups are created similarly to composite shapes. The difference is that groups can contain only shapes. The following example creates a group, which contains three shapes:

NGroup group = new NGroup();

// create ellipse
NEllipseShape ellipse = new NEllipseShape(0, 0, 100, 100);
ellipse.Text = "Ellipse";
group.Shapes.AddChild(ellipse);

// create rectangle
NRectangleShape rect = new NRectangleShape(150, 0, 100, 100);
rect.Text = "Rectangle";
group.Shapes.AddChild(rect);

// create line
NLineShape line = new NLineShape(0, 150, 100, 250);
line.Text = "Line";
group.Shapes.AddChild(line);

// update the model bounds of the group
group.UpdateModelBounds();

Dim group As New NGroup()

' create ellipse
Dim ellipse As New NEllipseShape(0, 0, 100, 100)
ellipse.Text = "Ellipse"
group.Shapes.AddChild(ellipse)

' create rectangle
Dim rect As New NRectangleShape(150, 0, 100, 100)
rect.Text = "Rectangle"
group.Shapes.AddChild(rect)

' create line
Dim line As New NLineShape(0, 150, 100, 250)
line.Text = "Line"
group.Shapes.AddChild(line)

' update the model bounds of the group
group.UpdateModelBounds()

It is important to remember that you must call the UpdateModelBounds method of the group once you have finished adding shapes to it. This is necessary in order for the group to adopt the bounds of the shapes it contains (see Models for more information about aggregate models bounds).

Since the user can select the shapes contained in a group, this allows him/her to delete all shapes of a group - i.e. make an empty group. 

You can protect a group from becoming empty with the help of the CanBeEmpty property. If this property is set to false the user will not be able to delete the last shape of a group.

You can also instruct groups to automatically destroy themselves when the become empty. This is specified by the AutoDestroy property. If this property is set to true the group will automatically destroy itself when its last child is removed.