title: Entity Framework - Custom logic in property setter
body: <p>Using an EF, Code First. In my class I have properties Quantity, Price and Amount. In setters of the first 2 properties I want to add logic to calculate amount. This works ok, but when I load entity next time, and Entity Framework fills properties with database values, than this custom logic is implemented too - and this is not good.
  How do you think is there any to implement custom logic only when user actually changes the value and not during object initialization?</p>