[Browsable(false)]
[DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)]
public Node SelectedNode {get; set;}

Property Value

Changing this value will make the previous value (if any) be not IsSelected, and will select the new value. Because this property is frequently set programmatically, it does not make sense to make this property the target of a OneWay data-binding.

Although Group inherits from Node, this property will be null if the selected part is a Group in order to make it easier to data-bind parts of your user interface differently for groups than for regular nodes.

Reference

Diagram Class
Diagram Members