private void OnModifyCommand()
 {
     if (SelectProductTypeEntity != null)
     {
         ProductTypeWindow productTypeWindow = new ProductTypeWindow(SelectProductTypeEntity);
         productTypeWindow.Closed += productTypeModify_Close;
         productTypeWindow.Show();
     }
 }
 private void OnAddCommand()
 {
     AddProductTypeEntity = new ProductTypeEntity();
     AddProductTypeEntity.ProductType = new ProductManager.Web.Model.product_type();
     ProductTypeWindow productTypeWindow = new ProductTypeWindow(AddProductTypeEntity);
     productTypeWindow.Closed += productTypeWindow_Closed;
     productTypeWindow.Show();
 }