Shadowing in C#

Question

I'm using C#. I have two classes A and B. B inherits from A. They both have a Foo() method (which is virtual in A). Now, if I have

A b = new B();
int x = b.Foo();

then Foo() from A is called. But if Foo() in B has the 'new' keyword, then again the Foo() from the base class is called. Then, why would I use shadowing?

Answer 1

Using new means exactly that: don't override.

The only effect of new is to suppress the compiler warning about hiding a base-member. It will never cause a different method to be called.

Answer 2

Knowing When to Use Override and New Keywords (C# Programming Guide)

Answer 3

The only case where I used method hiding is when I want to return a derived type in the derived class (the actual object being returned from both methods should be identical here). Of course this is only a hack around C#s lack of result type covariance.

Answer 4

It's quite useful with polymorphism.

This post might be a good start.
Hasan Khan also posted a good one that I was going to mention (no need anymore).
This other post might be of help too.