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POGeneric Types with Abstract classes and Interfaces
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2013-01-14T19:35:44.400
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2013-01-14T19:47:39.163
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I have three classes, one base class which takes a generic type that must be a subclass of an abstract class which in turn takes a generic type that must implement an interface. For testing I have a form which will initiate the base class giving a subclass of the abstract class and an implementation of the interface. Here are my class declarations, and call to the base class constructor. <pre><code> public class BaseClass<AC_IC> where AC_IC : AbstractClass<InterfaceClass> public abstract class AbstractClass<IC> where IC: InterfaceClass public interface InterfaceClass public class ExtendsAbstractClass<II> : AbstractClass<InterfaceClass> public class ImplementsInterface : InterfaceClass vBC = new BaseClass<ExtendsAbstractClass<ImplementsInterface>>(); </code></pre> I believed I would be able to create instances of both of the inheriting/implementing classes from within the BaseClass and AbstractClass using the following calls (only one class will have parameters in the constructor) <pre><code> (AC_IC) Activator.CreateInstance(typeof(AC_IC), new object[] { vParameter}); (II) Activator.CreateInstance(typeof(II)); </code></pre> EDIT: The above calls are within the BaseClass and AbstractClass and therefore do not know which classes I will use subsequently, so cannot be specified by class name, there may be many different pairs of classes for a range of implementations. For both of these constructor calls I get the errors 'Cannot create an instance of an abstract class' & 'Cannot create an instance of an interface'. How can I let the compiler know that the classes that I am passing as the generic types are subclassess of the classes in the <code>where</code> clauses and so can be created. Any ideas community???
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<c#><generics><inheritance>
Title
Generic Types with Abstract classes and Interfaces
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1. USColin Steel
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