How to find all the classes which implement a given interface?

Question

Under a given namespace, I have a set of classes which implement an interface. Let\'s call it ISomething. I have another class (let\'s call it CClass

Answer 1

Maybe we should go this way

foreach ( var instance in Assembly.GetExecutingAssembly().GetTypes().Where(a => a.GetConstructor(Type.EmptyTypes) != null).Select(Activator.CreateInstance).OfType() ) 
   instance.Execute();