"Entity Component System Implementation with Extension Methods"

// ENTITY BASE CLASS
public class Entity {
     
}
 
// COMPONENTS (INTERFACES)
public interface ITangibleEntity { }
public interface IModelledEntity : ITangibleEntity { }
public interface IAudibleEntity : ITangibleEntity { }
 
// COMPONENTS (EXTENSION METHOD IMPLEMENTATIONS)
public static class ComponentExtensions {
    // ITangibleEntity
    public static Vector3 GetPosition(this ITangibleEntity @this) {
        // TODO implement this
    }
    public static void SetPosition(this ITangibleEntity @this, Vector3 newPosition) {
        // TODO implement this
    }
    public static Vector3 GetVelocity(this ITangibleEntity @this) {
        // TODO implement this
    }
    public static void SetVelocity(this ITangibleEntity @this, Vector3 newVelocity) {
        // TODO implement this
    }
 
    // IModelledEntity
    public static ModelReference GetModel(this IModelledEntity @this) {
        // TODO implement this
    }
    public static void SetModel(this IModelledEntity @this, ModelReference newModel) {
        // TODO implement this
    }
    public static float GetScaling(this IModelledEntity @this) {
        // TODO implement this
    }
    public static void SetScaling(this IModelledEntity @this, float newScaling) {
        // TODO implement this
    }
    public static bool CameraCanSeeThis(this IModelledEntity @this, Camera camera) {
        return !PhysicsSystem.RayTest(camera.Position, GetPosition(@this)).IsObscured;
    }
 
    // IAudibleEntity
    public static SoundReference GetSound(this IModelledEntity @this) {
        // TODO implement this
    }
    public static void SetSound(this IModelledEntity @this, SoundReference newSound) {
        // TODO implement this
    }
    public static float GetSoundRadius(this IModelledEntity @this) {
        // TODO implement this
    }
    public static void SetSoundRadius(this IModelledEntity @this, float newSoundRadius) {
        // TODO implement this
    }
    public static bool CameraCanHearThis(this IModelledEntity @this, Camera camera) {
        return GetSoundRadius(@this) > Vector3.Distance(camera.Position, GetPosition(@this));
    }
}


Code snippet taken from "Simulating Multiple Inheritance In C#".