public void ChangeUnitPrice(Decimal unitPrice)
{
if(_unitsInStock > 0)
{
throw new InvalidOperationException("Cannot change unit price while there are still units in stock.");
}
var e = new ProductUnitPriceChanged(Id, unitPrice);
ApplyEvent(e);
}
private void ProductUnitPriceChangedEventHandler(ProductUnitPriceChanged e)
{
_unitPrice = e.UnitPrice;
}
