CouchBase Lite Prefix Saerch Issue

gistfile1.cs

            const string myprop = "myprop";
            const string myvalue = "myvalue";

            var manager = new Manager(new System.IO.DirectoryInfo(@"C:\temp\cbldb"), ManagerOptions.Default);
            var db = manager.GetDatabase("test");

            var newdoc = db.CreateDocument();
            var props = new Dictionary<string, object>
            {
                {myprop, myvalue }
            };
            var rev = newdoc.PutProperties(props);
            Debug.Assert(rev != null);


            //
            // View: [assetTagNumber]
            var view = db.GetView("view1");
            view.SetMap((doc, emit) =>
            {
                emit(doc[myprop], null);

            }, "201");
            Console.WriteLine("Refreshing view");
            view.CreateQuery().Run().MoveNext();
            Console.WriteLine("View refesh done");

            Console.WriteLine("Query view...");
            var myquery = view.CreateQuery();

            //string prefix = myvalue; // this outputs results
            string prefix = myvalue.Substring(0, myvalue.Length - 1); // this does NOT output results
            const string highUnicodeChar = "\uFFFE";

            myquery.StartKey = prefix;
            myquery.EndKey = prefix + highUnicodeChar;
            Console.WriteLine("Going to search for items with key in the range of: {0} - {1}", myquery.StartKey, myquery.EndKey);

            myquery.Prefetch = true;
            foreach (var item in myquery.Run())
            {
                Console.WriteLine("DocumentId: {0}; myprop: {1}",
                    item.DocumentId,
                    item.DocumentProperties[myprop]
                );
            }