Unity3d中的多态

Question

i need some help. I dont know if this possible:

I have 2 Scripts, the interactBase and the interactRock script.

The interactRock script extends the interactBase Script.

interactRock overwrites the function "interact()"

So i try to get the reference of the Object and call the function of the child.

But it dosent seems to work. Maybe u can help me?

Code:

interactBase:

    using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class interactBase : MonoBehaviour {

    public interactBase(){

    }

    // Use this for initialization
    void Start () {

    }

    // Update is called once per frame
    void Update () {

    }

    public void interact(){

    }
}

rockInteract:

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class rockInteract : interactBase {
    public bool triggered;

    public rockInteract(){
    }

    // Use this for initialization
    void Start () {
        triggered = false;
    }

    // Update is called once per frame
    void Update () {

    }

    public new void interact(){
        triggered = true;
        print ("working");
    }
}

The Calling Script:

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class triggerScript : MonoBehaviour {
    Animator anim;
    SpriteRenderer sprite;
    public bool triggered;
    public GameObject toTrigger;
    interactBase baseFunc;

    // Use this for initialization
    void Start () {
        anim = GetComponent<Animator> ();
        sprite = GetComponent<SpriteRenderer> ();
        triggered = false;

        baseFunc = toTrigger.GetComponent<interactBase>(); 
        print (baseFunc);
    }

    // Update is called once per frame
    void Update () {
        transform.position += Vector3.zero;
        if (triggered == true) {
            //print (baseFunc.interact ());
            baseFunc.interact ();
            triggered = false;
        }
    }
}

Thank you

Answer 1

The issue is that you need to define the base interact as

virtual void interact()

and the child as

override void interact

for the child interact to be called through a base class pointer. Using new does not accomplish that.

new really means "child has its very own method, which just happens to have the same name, as an entirely different method in the base class. This new method should be called when you use a child pointer but not when you use a base pointer, since base has its own method with that name". Virtual and override means "child has a different version of the same method and that is the one to call regardless of what type of pointer you use to this class".