SetParameter.cs

using (Transaction tran = new Transaction(doc, "Set Parameter"))
            {
                tran.Start();
                foreach (Element e in elements)
                {
                    
                    Parameter p = e.get_Parameter(BuiltInParameter.ALL_MODEL_INSTANCE_COMMENTS);
                    p?.Set(_viewModel.TxtStatus);
                    e.Dispose();
                }
                tran.Commit();
            }