原文地址 using System; using System.Collections.Generic; using System.Linq; using UnityEngine; using System.Collections;

[RequireComponent(typeof(GUIText))] public class Hijack : MonoBehaviour {

//This will hold the counting up coroutine IEnumerator _countUp; //This will hold the counting down coroutine IEnumerator _countDown; //This is the coroutine we are currently //hijacking IEnumerator _current;

//A value that will be updated by the coroutine //that is currently running int value = 0;

void Start() { //Create our count up coroutine _countUp = CountUp(); //Create our count down coroutine _countDown = CountDown(); //Start our own coroutine for the hijack StartCoroutine(DoHijack()); }

void Update() { //Show the current value on the screen guiText.text = value.ToString(); }

void OnGUI() { //Switch between the different functions if(GUILayout.Button("Switch functions")) { if(_current == _countUp) _current = _countDown; else _current = _countUp; } }

IEnumerator DoHijack() { while(true) { //Check if we have a current coroutine and MoveNext on it if we do if(_current != null && _current.MoveNext()) { //Return whatever the coroutine yielded, so we will yield the //same thing yield return _current.Current; } else //Otherwise wait for the next frame yield return null; } }

IEnumerator CountUp() { //We have a local increment so the routines //get independently faster depending on how //long they have been active float increment = 0; while(true) { //Exit if the Q button is pressed if(Input.GetKey(KeyCode.Q)) break; increment+=Time.deltaTime; value += Mathf.RoundToInt(increment); yield return null; } }

IEnumerator CountDown() { float increment = 0f; while(true) { if(Input.GetKey(KeyCode.Q)) break; increment+=Time.deltaTime; value -= Mathf.RoundToInt(increment); //This coroutine returns a yield instruction yield return new WaitForSeconds(0.1f); } }

}