嘗試了解 Unity Co-rotine 怎樣控 IEnumerator 

為了理解 Coroutine 怎樣處理資料, 認真的研究一下 IEnumerator 
嘗試在不使用 Unity StartCoroutine() 的情況下, 是怎樣自己控制執行的, 測試了一下.

就只是 Unity 自己定的 YieldInstruction 有點麻煩, 要自己想辦法處理甚麼時候結束..
reflection 可能是一條出路? 

 

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

public class TestCoroutine : MonoBehaviour
{
    private IEnumerator iter;
    private void OnEnable()
    {
        iter = MyEnumerator();
        Debug.ClearDeveloperConsole();
    }

    private IEnumerator MyEnumerator()
    {
        var a = 1;
        var b = 2;
        var c = -1;
        Debug.Log($"Step 1, A{a} + b{b} = C{c}");
        yield return "First block";


        c = a + b;
        Debug.Log($"Step 2, A{a} + b{b} = C{c}");
        yield return 2;

        c = 10000;
        Debug.Log($"Step 3, A{a} + b{b} = C{c}");

        yield return new WaitForSeconds(3f);
        Debug.LogWarning("BOOM ! 3 second.");
    }

    object lastObj = null;
    public void Update()
    {
        bool skip = lastObj is YieldInstruction;

        if (!(skip || Input.GetKeyUp(KeyCode.Space)))
            return;

        if (iter.MoveNext())
        {
            lastObj = iter.Current;
            if (lastObj == null)
            {

            }
            else if (lastObj is CustomYieldInstruction cy)
            {
                // cy.keepWaiting;
                if (cy is WaitWhile) { }
                else if (cy is WaitUntil) { }
                else if (cy is WaitForSecondsRealtime) { }
            }
            else if (lastObj is YieldInstruction u3d)
            {
                // need to handle unity3d's WaitFor family.
                Debug.Log($"U3D waiting {u3d.GetType()}");
                if (u3d is WaitForSeconds wfs)
                {
                    Debug.Log(wfs);
                }
                else if (u3d is WaitForEndOfFrame) { }
                else if (u3d is WaitForFixedUpdate) { }
            }
            else if (lastObj is string str)
            {
                Debug.Log($"It's str = {str}");
            }
            else if (lastObj is int i)
            {
                Debug.Log($"It's int = {i}");
            }
            else
            {
                Debug.Log($"What is this ? {lastObj.GetType()}");
            }
        }

        lastObj = null;
    }
}