void productTypeWindow_Closed(object sender, EventArgs e)
        {
            ProductTypeWindow productTypeWindow = sender as ProductTypeWindow;

            if (productTypeWindow.DialogResult == true)
            {
                ProductTypeEntityList.Add(AddProductTypeEntity);
                systemManageDomainContext.product_types.Add(AddProductTypeEntity.ProductType);
                OnSaveCommand();
            }
        }
        public void LoadData()
        {
            IsBusy = true;
            systemManageDomainContext = new SystemManageDomainContext();
            systemManageDomainContext.PropertyChanged -= systemManageDomainContext_PropertyChanged;
            systemManageDomainContext.PropertyChanged += systemManageDomainContext_PropertyChanged;
            ProductTypeEntityList.Clear();
            LoadOperation <ProductManager.Web.Model.product_type> loadOperationDepartment =
                systemManageDomainContext.Load <ProductManager.Web.Model.product_type>(systemManageDomainContext.GetProduct_typeQuery());

            loadOperationDepartment.Completed += loadOperationProductType_Completed;
        }
        private void loadOperationProductType_Completed(object sender, EventArgs e)
        {
            ProductTypeEntityList.Clear();
            LoadOperation loadOperation = sender as LoadOperation;

            foreach (ProductManager.Web.Model.product_type product_type in loadOperation.Entities)
            {
                ProductTypeEntity productTypeEntity = new ProductTypeEntity();
                productTypeEntity.ProductType = product_type;
                productTypeEntity.Update();
                ProductTypeEntityList.Add(productTypeEntity);
            }
            UpdateChanged("ProductTypeEntityList");
            IsBusy = false;
        }