Question

I keep getting StackOverFlowException whenever I instantiate an instance of A class. I know it has got something to do with the fact that A.b field is of type derived from class A. But why would that cause an exception?

static void Main(string[] args)
{
     A a = new A(); // exception
}

class A 
{
    private B b = new B();
}

class B:A {}

thank you

Answer 1

Here is what is happening under the hood

1. Create a new instance of A
2. As a consequence it creates an instance of B for the private field b
3. B derives from A and hence has it’s own field b. At this point it goes back to step #2 and repeats until a stack overflow occurs