Hi,

You should just mark the relevant methods as abstract in the abstract class. That way any sub-class must explicitly implement the method. Eg.

    public abstract class Test 
    {
        protected abstract int LoadPageData();
       
   }

    public class Test2 : Test
    {
    }

The above will not compile unless the LoadPageData() method is implemented in Test2.....

HTH,
Viv


>Hello Viv, I'm probably going about this the wrong way but !, what I'm trying to achieve is to force subclasses of my TabPage class to implement some methods ( i.e. the three shown in my code ) and I thought an Interface was the way to go , but if I have to mark the methods as virtual in my base class to get rid of the compiler warning ( I know it's there for a reason :-) ), I lose the power to force the imlementation of the methods in the subclasses. I suppose I could dispense with the the abstract base class and inherit directly from my base tab class every time and implement the interface on every subclass (ugh !!) any ideas ?