Code

Rect r = node.Bounds;
float centerx = r.Left + r.Width / 2;
float dist = 10;
SetLinkPoints(link,
	new Point(centerx, r.Top),
	new Point(centerx, r.Top - dist),
	new Point(r.Right + dist, r.Top - dist),
	new Point(r.Right + dist, r.Bottom + dist),
	new Point(centerx, r.Bottom + dist),
	new Point(centerx, r.Bottom));

private void SetLinkPoints(DiagramLink link, params Point[] points)
{
	link.AutoRoute = false;
	link.Style = LinkStyle.Cascading;
	link.SegmentCount = (short)(points.Length - 1);
	link.ControlPoints.Clear();
	link.ControlPoints.AddRange(points);
	link.UpdateFromPoints();
}
 

Code

private void SetLinkPoints(DiagramLink link, params Point[] points)
{
	link.AutoRoute = false;
	link.SegmentCount = (short)(points.Length - 1);
	link.Style = LinkStyle.Cascading;
	link.ControlPoints.Clear();
	link.ControlPoints.AddRange(points);
	link.UpdateFromPoints();
}
 

Code

private void OnLinkCreated(object sender, LinkEventArgs e)
{
	if (e.Link.Origin == e.Link.Destination)
	{
		Rect r = e.Link.Origin.Bounds;
		float centery = (float)(r.Top + (r.Height / 2));
		var link = e.Link;
		var points = link.ControlPoints.Clone();

		var newO = new Point(r.Right, centery);
		var rt = new RotateTransform(90, newO.X, newO.Y);
		var o = points[0];
		var offset = newO - o;

		for (int i = 0; i < points.Count; ++i)
			points[i] = rt.Transform(points[i] + offset);

		link.ControlPoints.Clear();
		link.ControlPoints.AddRange(points);
		link.UpdateFromPoints();
	}
}