// works in Revit Structure 2009 API, but not in 2010: bool IsColumnRound( FamilySymbol symbol) { GenericFormSet solid = symbol.Family.SolidForms; GenericFormSetIterator i = solid.ForwardIterator(); i.MoveNext(); Extrusion extr = i.Current as Extrusion; CurveArray cr = extr.Sketch.CurveLoop; CurveArrayIterator i2 = cr.ForwardIterator(); i2.MoveNext(); String s = i2.Current.GetType().ToString(); return(s.Contains("Arc")); }