C# Programming - Interfaces - Discussion

The right answer is : E.

The compiler will report an error since the interface IMyInterface is only partially implemented.

Checked by code.

Application does not implement interface member 'Application.IMyInterface.fun2()'. The correct answer is E.

@Vani if class is abstract you can do this:

interface IMyInterface
{
void fun1();
int fun2();
}
abstract class MyClass : IMyInterface
{
public abstract void fun1();
public abstract int fun2();
}
or implement one of this:
abstract class MyClass : IMyInterface
{
void IMyInterface.fun1()
{Console.WriteLine("Hello world"); }
public abstract int fun2();
}

[E] must be the correct option. As its not an abstract class. It has to implement all the methods of the interface. Here, it will report an error.

Even if implementing class is abstract we still get same error that all the methods must be implemented. Please check below code and explain?

interface IMyInterface
{
void fun1();
int fun2();
}
abstract class MyClass : IMyInterface
{
void IMyInterface.fun1()
{ }
//int IMyInterface.fun2()
//{ return 1; }
}

Interface types, not being classes, are not derived from object. They are all convertible to object, to be sure, because we know that at runtime the instance will be a concrete type. But interfaces only derive from other interface types, and object is not an interface type.

for more follow below link: http://blogs.msdn.com/b/ericlippert/archive/2009/08/06/not-everything-derives-from-object.aspx

In above code, the Implementing class is not a abstract class, so answer is E.

OOPs concept says that the class which is inheriting Interface must implement all the members in that Interface.

If that class doesn't want to implement all methods of Interface then it should declare itself as abstract class.

In above code, the Implementing class is not a abstract class, so answer is E