public void AddAndRemoveExtents()
        {
            if (!TestHelper.GetDlcPath(out string dlcPath))
            {
                return;
            }

            var ope = new UoeDatabaseOperator(dlcPath);

            var tgtDb = GetDb("extents");

            ope.Create(tgtDb);
            Assert.IsTrue(tgtDb.Exists());

            var stPath = Path.Combine(TestFolder, "extents_add.st");

            File.WriteAllText(stPath, $"d \"Data Area\" \"{TestFolder}\"");

            ope.AddStructureDefinition(tgtDb, stPath);

            try {
                ope.Start(tgtDb);
                File.WriteAllText(stPath, $"d \"New Area\" \"{TestFolder}\"");
                ope.AddStructureDefinition(tgtDb, stPath);
            } finally {
                ope.Stop(tgtDb);
            }

            Assert.IsTrue(File.Exists(Path.Combine(TestFolder, "extents_7.d1")));
            Assert.IsTrue(File.Exists(Path.Combine(TestFolder, "extents_8.d1")));

            ope.RemoveStructureDefinition(tgtDb, "d", "Data Area");

            Assert.IsFalse(File.Exists(Path.Combine(TestFolder, "extents_7.d1")));
        }