private Notification(SupplierOffer supplierOffer)
{
if (supplierOffer == null)
{
throw new ArgumentNullException();
}
SupplierOffer = supplierOffer;
DateTime = DateTime.Now;
}
public static Notification OfferCreated(SupplierOffer supplierOffer)//factoty method
{
return(new Notification(supplierOffer));
}