[CONNECT C#.NET] ECQuery WhereClause for ECProperties in nested ECClasses help

		public static bool GadgetTest(ElementId existingElmId)
		{
			int verMajor = 1, verMinor = 0;
			ECSchema schema = new ECSchema("Gadget", verMajor, verMinor, "aSa.Studio");

			ECClass dataClass = new ECClass("GadgetStuff"); // Main Class CANNOT be "IsStruct" type.
			dataClass.DisplayLabel = "Gadget Stuff";

			ECClass valClass = new ECClass("ValuesClass", true); // IsStruct
			var prop = new ECProperty("Tag", ECObjects.StringType);
			prop.DisplayLabel = "Gadget Tag";
			prop.IsReadOnly = true;
			valClass.Add(prop);
			prop = new ECProperty("Inventor", ECObjects.StringType);
			prop.DisplayLabel = "Inventor";
			prop.IsReadOnly = true;
			valClass.Add(prop);
			//schema.AddClass(valClass); // not necessary - gets added with dataClass

			prop = new ECProperty("Values", valClass);
			dataClass.Add(prop);

			ECClass keysClass = new ECClass("KeysClass", true); // IsStruct
			prop = new ECProperty("GrpNum", ECObjects.IntegerType);
			prop.IsReadOnly = true;
			keysClass.Add(prop);
			//schema.AddClass(keysClass); // not necessary - gets added with dataClass

			prop = new ECProperty("Keys", keysClass);
			dataClass.Add(prop);

			var vProp = new ECProperty("Version", ECObjects.StringType);
			vProp.DisplayLabel = "Version";
			vProp.IsReadOnly = true;
			dataClass.Add(vProp);
			// dataClass now contains nested ValuesClass, nested KeysClass, and non-nested Version property.
			schema.AddClass(dataClass);
#if DEBUG
			ECSchemaXmlStringWriter xmlWriter = new ECSchemaXmlStringWriter();
			string xml = xmlWriter.Serialize(schema); // to view schema as XML during Debugging
#endif
			ImportSchemaOptions iOpts = new ImportSchemaOptions((ushort)DgnECProviderId.ECXData);
			SchemaImportStatus stat;
			if (SchemaImportStatus.Success != (stat = DgnECManager.Manager.ImportSchema(schema, Session.Instance.GetActiveDgnFile(), iOpts)))
			{
				return false;
			}

			Element elm = Session.Instance.GetActiveDgnModel().FindElementById(existingElmId);
			DgnECInstanceEnabler enabler = DgnECManager.Manager.ObtainInstanceEnabler(Session.Instance.GetActiveDgnFile(), dataClass);// schema.GetClass("GadgetStuff"));
			StandaloneECDInstance wip = new StandaloneECDInstance(dataClass);
			IDgnECInstance instGadget = enabler.CreateInstanceOnElement(elm, wip, false); // instance does NOT own element
			instGadget["Values.Tag"].StringValue = "FirstGadget";
			instGadget["Values.Inventor"].StringValue = "aSa";
			instGadget["Keys.GrpNum"].IntValue = 10;
			instGadget["Version"].StringValue = verMajor.ToString() + "." + verMinor.ToString();
			instGadget.WriteChanges();

			FindInstancesScope scope = FindInstancesScope.CreateScope(Session.Instance.GetActiveDgnFile(), new FindInstancesScopeOption(DgnECHostType.Element, false));

			// This query and FindInstances works fine. The WhereClause is set up to look for the non-nested Version property.
			var query = new ECQuery(dataClass);
			PropertyExpression exp = new PropertyExpression(RelationalOperator.EQ, dataClass["Version"], "1.0");
			query.WhereClause.Add(exp);
			query.SelectClause.SelectAllProperties = true;

			var dgnInstances = DgnECManager.Manager.FindInstances(scope, query);
			if (null != dgnInstances && 0 < dgnInstances.Count())
			{
				foreach (var inst in dgnInstances)
				{
					string msg = string.Format("Tag = {0}\nInventor = {1}\n", inst["Values.Tag"].StringValue, inst["Values.Inventor"].StringValue);
					MessageBox.Show(msg, "By NON-Nested Property");
				}
			}

			// I can NOT get this query and FindInstances to work at all. The WhereClause is set up to look for a property in a nested (struct) class.
			// I have tried a lot of ways, some I have shown commented here, adding multiple classes to the query, etc., it just does not seem to work.
			// Is this a bug or am I doing something wrong??
			query = new ECQuery(dataClass);
			//exp = new PropertyExpression(RelationalOperator.EQ, dataClass["Keys.GrpNum"], 10); // does not work -> Exception: dataClass["Keys.GrpNum"] is null
			//exp = new PropertyExpression(RelationalOperator.EQ, dataClass["Values.Inventor"], "aSa); // does not work -> Exception: dataClass["Values.Inventor"] is null
			//exp = new PropertyExpression(RelationalOperator.EQ, keysClass["GrpNum"], 10); // does not work -> just doesn't find anything
			//exp = new PropertyExpression(RelationalOperator.EQ, valClass["Inventor"], "aSa"); // does not work -> just doesn't find anything

			//List<IECClass> classes = new List<IECClass>();
			//foreach (IECClass ecClass in schema.GetClasses())
			//	classes.Add(ecClass);
			//query = new ECQuery(classes);

			foreach (var p in schema.GetProperties())
			{
				if (p.Name == "Inventor")
				{
					prop = p as ECProperty;
					break;
				}
			}
			
			try
			{
				exp = new PropertyExpression(RelationalOperator.EQ, prop, "aSa"); // does not work -> just doesn't find anything
				query.WhereClause.Add(exp);
				//var where = QueryHelper.CreateWhereCriteriaForStringFilter(prop, "aSa", RelationalOperator.LIKE); // does not work - just doesn't find anything
				//query.WhereClause.Add(where);
				//QueryHelper.WherePropertyExpressions(query, "Inventor", RelationalOperator.EQ, "aSa"); // does not work - just doesn't find anything
			}
			catch (Exception e)
			{
				string msg = e.Message;
			}
			query.SelectClause.SelectAllProperties = true;

			dgnInstances = DgnECManager.Manager.FindInstances(scope, query);
			if (null != dgnInstances && 0 < dgnInstances.Count())
			{
				foreach (var inst in dgnInstances)
				{
					string msg = string.Format("Tag = {0}\nInventor = {1}\n", inst["Values.Tag"].StringValue, inst["Values.Inventor"].StringValue);
					MessageBox.Show(msg, "By Nested Property");
				}
			}
			else
			{
				MessageBox.Show("Well, THAT didn't work!", "By Nested Property");
				return false;
			}

			return true;
		}