C# EntityManager.Clear方法代码示例

        public async Task QueryWithAFilter()
        {
            var manager = new EntityManager(_serviceName);

            // Metadata must be fetched before CreateEntity() can be called
            await manager.FetchMetadata();

            // Ensure there is at least one active todo item named Wine in the database
            var wines = await new EntityQuery<TodoItem>().Where(td => td.Description == "Wine" && !td.IsArchived && !td.IsDone).Execute(manager);
            if (!wines.Any()) {
                var newWine = manager.CreateEntity<TodoItem>(new {Description = "Wine"});
                await manager.SaveChanges();
            }
            manager.Clear();

            //Snippet1
            var query1 = new EntityQuery<TodoItem>();
            var allTodos = await manager.ExecuteQuery(query1);
            Assert.IsTrue(allTodos.Any(), "No TodoItems in the database");
            
            //Snippet2
            var query2 = query1.Where(td => !td.IsArchived);
            var unarchivedTodos = await manager.ExecuteQuery(query2);
            Assert.IsTrue(unarchivedTodos.Any(), "No unarchived TodoItems in the database");

            //Snippet3
            var query3 = query1.Where(td => !td.IsArchived && !td.IsDone);
            var activeTodos = await manager.ExecuteQuery(query3);
            Assert.IsTrue(activeTodos.Any(), "No active TodoItems in the database");

            //Snippet4
            var query4 = query1.Where(td => td.Description.Contains("Wine"));
            var wineTodos = await manager.ExecuteQuery(query4);
            Assert.IsTrue(allTodos.Any(), "No Wine TodoItems in the database");

            //Snippet5
            // Execute above query locally
            var localWineTodos = manager.ExecuteQueryLocally(query4);
            Assert.AreEqual(wineTodos.Count(), localWineTodos.Count(), "Got " + localWineTodos.Count() + " local wine TodoItems");
        }

        public async Task ImportChangedEntityAndRestoreItsOriginalState()
        {
            var manager = new EntityManager(_serviceName);
            await manager.FetchMetadata(); // Metadata must be fetched before CreateEntity() can be called

            // Suppose we are editing a customer
            const string originalCustomerName = "Foo";
            var customer =
                manager.CreateEntity<Customer>(new {CustomerID = Guid.NewGuid(), CompanyName = originalCustomerName},
                                               EntityState.Unchanged);

            // We change his CompanyName
            customer.CompanyName = "Bar";

            // We export and stash these changes offline
            // because we are not ready to save them
            // (in the test we just export)
            var exportData = manager.ExportEntities();

            // We re-run the app later with a clean manager
            manager.Clear();

            var imported = manager.ImportEntities(exportData);
            customer = imported.ImportedEntities.Cast<Customer>().First();

            // We want to revert our changes and restore the customer to its original state
            customer.EntityAspect.RejectChanges();

            Assert.AreEqual(originalCustomerName, customer.CompanyName);
        }

        public async Task ExportImportSelectedEntities()
        {
            var manager = new EntityManager(_serviceName);
            var manager2 = new EntityManager(_serviceName);
            await PrimeCache(manager);
            var customers = manager.GetEntities<Customer>().ToList();

            var exportData1 = manager.ExportEntities(new IEntity[] {customers[0]}); // array with 1 customer
            var importData1 = manager2.ImportEntities(exportData1);
            Assert.AreEqual(1, importData1.ImportedEntities.Count);
            manager2.Clear();

            var exportData2 = manager.ExportEntities(new IEntity[] {customers[0], customers[1]}); // array of 2 customers
            var importData2 = manager2.ImportEntities(exportData2);
            Assert.AreEqual(2, importData2.ImportedEntities.Count);
            manager2.Clear();

            Assert.AreEqual(0, manager.GetChanges().Count());
            customers.First().City = "Paris";
            var exportData3 = manager.ExportEntities(manager.GetChanges()); // all pending changes
            var importData3 = manager2.ImportEntities(exportData3);
            Assert.AreEqual(1, importData3.ImportedEntities.Count);
            manager2.Clear();

            var selectedCustomerQuery = new EntityQuery<Customer>().Where(customer => customer.City.StartsWith("P"));
            var selectedCustomers = manager.ExecuteQueryLocally(selectedCustomerQuery); // cache-only query returns synchronously
            var exportData4 = manager.ExportEntities(selectedCustomers); // the 'P' customers 
            var importData4 = manager2.ImportEntities(exportData4);
            Assert.AreEqual(1, importData4.ImportedEntities.Count);
        }