public Result Execute( ExternalCommandData commandData, ref string message, ElementSet elements) { UIApplication app = commandData.Application; Document doc = app.ActiveUIDocument.Document; try { #region 2.4 Retrieve all doors, move them and widen them: FilteredElementCollector doors = LabUtils.GetFamilyInstances( doc, BuiltInCategory.OST_Doors); using (Transaction tx = new Transaction(doc)) { tx.Start("Move Doors Up"); // move doors up 0.2 feet: XYZ v = 0.2 * XYZ.BasisZ; foreach (FamilyInstance door in doors) { //doc.Move( door, v ); // 2011 ElementTransformUtils.MoveElement(doc, door.Id, v); // 2012 // widen doors by one foot by changing parameter value: Parameter p = door.Symbol.get_Parameter( BuiltInParameter.WINDOW_WIDTH); if (null != p) { double width = p.AsDouble(); width += 1.0; p.Set(width); } } tx.Commit(); } return(Result.Succeeded); #endregion // 2.4 Retrieve all doors, move them and widen them } catch (Exception ex) { message = ex.Message; return(Result.Failed); } }