c# - Unity 4.6 无法将类型 `UnityEngine.Component' 隐式转换为 `DamageInterface'

Question

我在尝试编译我的游戏时遇到问题，问题源于我的损坏界面脚本和我的射弹脚本。控制台报错代码如下。

Assets/Scripts/Projectile.cs(32,33):错误 CS0266:无法将类型 UnityEngine.Component' 隐式转换为 DamageInterface'。存在显式转换(是否缺少强制转换？)

DamageInterface.cs

using UnityEngine;
using System.Collections;
//damage interface

public interface DamageInterface {

    void TakeHit (float damage, RaycastHit hit);

}

Projectile.cs

using UnityEngine;
using System.Collections;

public class Projectile : MonoBehaviour {

    public LayerMask collisionMask; //detect what layer projectile collides with 
    float speed = 10;
    float damage = 1;

    public void SetSpeed(float newSpeed) {
        speed = newSpeed;
    }

    void Update () {
        float moveDistance = speed * Time.deltaTime;
        CheckCollisions (moveDistance);
        transform.Translate (Vector3.forward * moveDistance);
    }


    void CheckCollisions(float moveDistance) { //raycast to detect collision
        Ray ray = new Ray (transform.position, transform.forward);
        RaycastHit hit;

        if (Physics.Raycast(ray, out hit, moveDistance, collisionMask)) {
            OnHitObject(hit);
        }
    }


    void OnHitObject(RaycastHit hit) {
        DamageInterface damageableObject = hit.collider.GetComponent(typeof(DamageInterface)); //ERROR RESIDES HERE
        if (damageableObject != null) {
            damageableObject.TakeHit(damage, hit); //damage + raycast hit
        }
        GameObject.Destroy (gameObject); //destroy projectile if enemy layer is hit
    } 
}

我相信我已经使用 typeof(T) 方法来获取我的界面组件，但我肯定遗漏了一些明显的东西。谢谢

错误存在于我的 Projectile.cs 中的这一行:

DamageInterface damageableObject = hit.collider.GetComponent(typeof(DamageInterface));

Answer 1

在 Unity5.x 中，您可以获取接口(interface)如下的组件:

IInterface myInterface = gameObject.GetComponent<IInterface>();

在旧版本中你需要执行转换:

 IInterface myInterface = (IInterface)gameObject.GetComponent(typeof(IInterface));

这是因为 GetComponent 返回一个组件而您的界面不是。该错误实际上告诉您该怎么做:

存在显式转换(是否缺少强制转换？)

是的，你错过了类型转换。