Unity的物理系統，處理碰撞事件，需要自行實現MonoBehaviour中的void OnTriggerEnter(Collider)等方法，MonoBehaviour的生命周期方法，有些不太常用，可能會經常不記得、或者打錯名字，調試還不容易找到原因，很不方便。  
我們可以把常用接口封裝起來，讓需要實現碰撞事件的類，繼承已經封裝好的類即可。
using System;
using UnityEngine;
[RequireComponent(typeof(Collider))]
public class ColliderListener : MonoBehaviour {
public ActiononTriggerEnter = delegate { };
public ActiononTriggerStay = delegate { };
public ActiononTriggerExit = delegate { };
public ActiononCollisionEnter = delegate { };
public ActiononCollisionStay = delegate { };
public ActiononCollisionExit = delegate { };
private void OnTriggerEnter(Collider other) {
onTriggerEnter(other);
}
private void OnTriggerStay(Collider other) {
onTriggerStay(other);
}
private void OnTriggerExit(Collider other) {
onTriggerExit(other);
}
private void OnCollisionEnter(Collision other) {
onCollisionEnter(other);
}
private void OnCollisionStay(Collision other) {
onCollisionStay(other);
}
private void OnCollisionExit(Collision other) {
onCollisionExit(other);
}
public virtual void Clear() {
onTriggerEnter = delegate { };
onTriggerStay = delegate { };
onTriggerExit = delegate { };
onCollisionEnter = delegate { };
onCollisionStay = delegate { };
onCollisionExit = delegate { };
}
}