private void TestItem()
        {
            int          hr = 0;
            ITuningSpace ts;

            hr = tsContainer.get_Item(1, out ts);
            DsError.ThrowExceptionForHR(hr);

            Debug.Assert(hr == 0, "ITuningSpaceContainer.get_Item");

            hr = tsContainer.put_Item(1, ts);
            DsError.ThrowExceptionForHR(hr);

            Debug.Assert(hr == 0, "ITuningSpaceContainer.put_Item");

            Marshal.ReleaseComObject(ts);
        }