不要在协程里做耗时的工作，会卡住整个游戏

以下是测试代码，分别用线程和协程实现

using System.Collections;
using System.Collections.Generic;
using System.IO;
using System.Threading;
using UnityEngine;
using UnityEngine.UI;

public class CoroutinTest : MonoBehaviour
{
    public Text t;
    int m_Count = 0;
    float m_second = 0;
    // Use this for initialization
    void Start ()
    {
        //StartCoroutine(CoroutineTest());

        new Thread(new ThreadStart(SubThread)).Start();
    }

    private void Update()
    {
        t.text = m_Count.ToString() + " " + m_second;
    }

    void SubThread()
    {
        while (true)
        {
            Thread.Sleep(1000);

            string strFile = "E:/MyTest/Unity2017/Assets/ColoutineTest.txt";

            //Debug.Log(string.Format("begin time : {0}", System.DateTime.Now.ToString("T")));

            long tmp = System.DateTime.Now.Ticks;

            for (int i = 0; i < 100; i++)
            {
                byte[] b = File.ReadAllBytes(strFile);
            }

            m_second = (System.DateTime.Now.Ticks - tmp) / 1000000;

            //Debug.Log(string.Format("end time : {0}", System.DateTime.Now.ToString("T")));

            m_Count++;
        }
    }

    IEnumerator CoroutineTest()
    {
        while (true)
        {
            yield return new WaitForSeconds(1f);

            string strFile = "E:/MyTest/Unity2017/Assets/ColoutineTest.txt";

            Debug.Log(string.Format("begin time : {0}", System.DateTime.Now.ToString("T")));

            long tmp = System.DateTime.Now.Ticks;

            for (int i = 0; i < 100; i++)
            {
                byte[] b = File.ReadAllBytes(strFile);
            }

            m_second = (System.DateTime.Now.Ticks - tmp) / 1000000;

            Debug.Log(string.Format("end time : {0} tick:{1}", System.DateTime.Now.ToString("T"), m_second));

            m_Count++;
        }
    }
}