It works fine with Davids code. You are only using part of it. The full code is:

protected bool CurveSegments(List<Curve> L, Curve crv, bool recursive)

{

if (crv == null) { return false; }

PolyCurve polycurve = crv as PolyCurve;

if (polycurve != null)

{

if (recursive) { polycurve.RemoveNesting(); }

Curve[] segments = polycurve.Explode();

if (segments == null) { return false; }

if (segments.Length == 0) { return false; }

if (recursive)

{

foreach (Curve S in segments)

{

CurveSegments(L, S, recursive);

}

}

else

{

foreach (Curve S in segments)

{

L.Add(S.DuplicateShallow() as Curve);

}

}

return true;

}

PolylineCurve polyline = crv as PolylineCurve;

if (polyline != null)

{

if (recursive)

{

for (int i = 0; i < (polyline.PointCount - 1); i++)

{

L.Add(new LineCurve(polyline.Point(i), polyline.Point(i + 1)));

}

}

else

{

L.Add(polyline.DuplicateCurve());

}

return true;

}

Polyline p;

if (crv.TryGetPolyline(out p))

{

if (recursive)

{

for (int i = 0; i < (p.Count - 1); i++)

{

L.Add(new LineCurve(p[i], p[i + 1]));

}

}

else

{

L.Add(new PolylineCurve§);

}

return true;

}

//Maybe it’s a LineCurve?

LineCurve line = crv as LineCurve;

if (line != null)

{

L.Add(line.DuplicateCurve());

return true;

}

//It might still be an ArcCurve…

ArcCurve arc = crv as ArcCurve;

if (arc != null)

{

L.Add(arc.DuplicateCurve());

return true;

}

//Nothing else worked, lets assume it’s a nurbs curve and go from there…

NurbsCurve nurbs = crv.ToNurbsCurve();

if (nurbs == null) { return false; }

double t0 = nurbs.Domain.Min;

double t1 = nurbs.Domain.Max;

double t;

int LN = L.Count;

do

{

if (!nurbs.GetNextDiscontinuity(Continuity.C1_locus_continuous, t0, t1, out t)) { break; }

Interval trim = new Interval(t0, t);

if (trim.Length < 1e-10)

{

t0 = t;

continue;

}

Curve M = nurbs.DuplicateCurve();

M = M.Trim(trim);

if (M.IsValid) { L.Add(M); }

t0 = t;

} while (true);

if (L.Count == LN) { L.Add(nurbs); }

return true;

}