Generic method with type constraints or base class parameter

Question

If I write a method accepting a parameter which derives from a BaseClass (or an interface), as far as I know there are two ways to achieve that:

voi         


        

Answer 1

When T is constrained to a base class, there is not really much difference apart from what has already been stated.

When T is constrained to an interface, the difference can be huge:

int FrobNonGeneric(IFrobbable frob) { //... }
int Frob(T frob) where T: IFrobbable { //... }

struct Frob: IFrobbable { ... }

FrobNonGeneric(new Frob()); //boxing!
Frob(new Frob()); //no boxing