C#: Specify that a function arg must inherit from one class, and implement an interface?

Question

I'm making a game where each Actor is represented by a GameObjectController. Game Objects that can partake in combat implement ICombatant. How can I specify that arguments to a combat function must inherit from GameObjectController and implement ICombatant? Or does this indicate that my code is structured poorly?

public void ComputeAttackUpdate(ICombatant attacker, AttackType attackType, ICombatant victim)

In the above code, I want attacker and victim to inherit from GameObjectController and implement ICombatant. Is this syntactically possible?

Answer 1

I'd say it probably indicates you could restructure somehow, like, have a base Combatant class that attacker and victim inherit from, which inherits from GameObjectController and implements ICombatant.

however, you could do something like

ComputeAttackUpdate<T,U>(T attacker, AttackType attackType, U victim)
      where T: ICombatant, GameObjectController
      where U: ICombatant, GameObjectController

Although I probably wouldn't.

Answer 2

Presumably all ICombatants must also be GameObjectControllers? If so, you might want to make a new interface IGameObjectController and then declare:

interface IGameObjectController
{
    // Interface here.
}

interface ICombatant : IGameObjectController
{
    // Interface for combat stuff here.
}

class GameObjectController : IGameObjectController
{
    // Implementation here.
}

class FooActor : GameObjectController, ICombatant
{
    // Implementation for fighting here.   
}