public void Load()
{
var expiration = TimeSpan.FromDays(1);
Categories = memoryCacheProvider.GetOrSet(CategoriesKey, SampleDataSource.GetCategories, expiration)
.ToList();
Courses = memoryCacheProvider.GetOrSet(CoursesKey, SampleDataSource.GetCourses, expiration)
.ToList();
Orders = memoryCacheProvider.GetOrSet(OrdersKey, () => new List <Order>(), expiration)
.ToList();
OrderItems = memoryCacheProvider.GetOrSet(OrderItemsKey, () => new List <OrderItem>(), expiration)
.ToList();
}
