Is it possible to override a method with a derived parameter instead of a base one?

Question

I\'m stuck in this situation where:

1. I have an abstract class called Ammo, with AmmoBox and Clip as chil

Answer 1

You can use composition with interface extensions instead of multiple-inheritance:

class Ammo {}
class Clip : Ammo {}
class AmmoBox : Ammo {}

class Firearm {}
interface IClipReloadable {}
interface IAmmoBoxReloadable {}

class ClipWeapon : Firearm, IClipReloadable, IAmmoBoxReloadable {}
class AmmoBoxWeapon : Firearm, IAmmoBoxReloadable {}

static class IClipReloadExtension {
    public static void Reload(this IClipReloadable firearm, Clip ammo) {}
}

static class IAmmoBoxReloadExtension {
    public static void Reload(this IAmmoBoxReloadable firearm, AmmoBox ammo) {}
}

So that you will have 2 definitions of Reload() method with Clip and AmmoBox as arguments in ClipWeapon and only 1 Reload() method in AmmoBoxWeapon class with AmmoBox argument.

var ammoBox = new AmmoBox();
var clip = new Clip();

var clipWeapon = new ClipWeapon();
clipWeapon.Reload(ammoBox);
clipWeapon.Reload(clip);

var ammoBoxWeapon = new AmmoBoxWeapon();
ammoBoxWeapon.Reload(ammoBox);

And if you try pass Clip to AmmoBoxWeapon.Reload you will get an error:

ammoBoxWeapon.Reload(clip); // <- ERROR at compile time