Question

I’m wondering if something like this is possible…

class Thing
{
        public Thing(int i)
        {
        }
}

class DerivedThing : Thing
{
        public DerivedThing(int i)
        {
        }
}

_thing = new Thing(0)

_derivedthing  = new Thing(1)

If you pass 0 you get a Thing, if you pass 1 you get a DerivedThing
This is not complete, just an illustration.. But basically I’m wondering if/how you could return different derived classes based on the value of a parameter passed to the baseclass constructor?
Or do you just need another bit of code which decides which constructor to call?

Answer 1

To answer your question: no, it is not possible. But…

You are actually looking for a Factory pattern. You can easily add a distinguishing if/case in a factory method and still have a relatively clean code.

Factory pattern description