Set Default Content Type Using CSOM Not Working

Question

I have created new content type in CSOM, i need to set the newly created content type as default content type for the custom created sharepoint list. I am using below code.

List aeList = ctx.Web.Lists.GetByTitle("Project Definition");
var currentCtOrder = aeList.ContentTypes;
ctx.Load(currentCtOrder, coll => coll.Include(
                                 ct => ct.Name,
                                 ct => ct.Id));
ctx.ExecuteQuery();

IList<ContentTypeId> reverseOrder = (from ct in currentCtOrder where ct.Name.Equals("Project Definition", StringComparison.OrdinalIgnoreCase) select ct.Id).ToList();
aeList.RootFolder.UniqueContentTypeOrder = reverseOrder;
aeList.RootFolder.Update();
aeList.Update();
ctx.ExecuteQuery();

But the code gives error saying "System.NotSupportedException:'Specified method is not supported'" while querying on line no. 5

Can someone help?

Answer 1

         static void Main(string[] args)
        {
            ClientContext ctx = new ClientContext("http://sp/sites/jerry");
            List list = ctx.Web.Lists.GetByTitle("Documents");
            ChangeContentTypeOrder(ctx, list);

        }
        private static void ChangeContentTypeOrder(ClientContext ctx, List list)
        {
            ContentTypeCollection currentCtOrder = list.ContentTypes;
            ctx.Load(currentCtOrder);
            ctx.ExecuteQuery();

            IList<ContentTypeId> reverceOrder = new List<ContentTypeId>();
            foreach (ContentType ct in currentCtOrder)
            {
                if (ct.Name.Equals("testct"))
                {
                    reverceOrder.Add(ct.Id);
                }
            }
            list.RootFolder.UniqueContentTypeOrder = reverceOrder;
            list.RootFolder.Update();
            list.Update();
            ctx.ExecuteQuery();
        }