How can I detect the right click on a node ?

private void diagram1_MouseUp(object sender, System.Windows.Forms.MouseEventArgs e)
{
   if (e.Button == MouseButtons.Right && this.diagram1.Controller.NodesHit.Count>0 &&this.diagram1.View.SelectionList.Count!=0)
    {
if(this.diagram1.View.SelectionList.First is FilledPath )
        {
this.contextMenu1.Show(this.diagram1,new Point(e.X,e.Y));
         }
     }
}
 

Private Sub diagram1_MouseUp(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles diagram1.MouseUp
   If e.Button = Windows.Forms.MouseButtons.Right AndAlso Me.diagram1.Controller.NodesHit.Count > 0 AndAlso Me.diagram1.View.SelectionList.Count <> 0 Then
       If TypeOf Me.diagram1.View.SelectionList.First Is FilledPath Then
Me.contextMenu1.Show(Me.diagram1, New Point(e.X, e.Y))
        End If
     End If
End Sub