Unity中实现倒计时的几种方式

1. Time.time

using UnityEngine;

public class TimeTest : MonoBehaviour
{
    public float secound = 10;

    void Update()
    {
        Timing();
    }

    private float nextTime = 1;
    private void Timing()
    {
        if (secound <= 0) return;
        if(Time.time >= nextTime)
        {
            secound -= 1;
            Debug.Log(secound);
            nextTime = Time.time + 1;
        }
    }
}

2. Time.deltaTime

using UnityEngine;

public class TimeTest : MonoBehaviour
{
    public float secound = 10;

    void Update()
    {
        Timing();
    }

    private float waitTime;
    private void Timing()
    {
        if (secound <= 0) return;
        waitTime += Time.deltaTime;
        if(waitTime >=1)
        {
            secound--;
            Debug.Log(secound);
            waitTime = 0;
        }
    }
}

3. InvokeRepeating

using UnityEngine;

public class TimeTest : MonoBehaviour
{
    public float secound = 10;

    void Start() => InvokeRepeating("Timing", 1, 1);

    private void Timing()
    {
        if (secound <= 0) return;
        secound--;
        Debug.Log(secound);
    }
}

4. 协程

using System.Collections;
using UnityEngine;

public class TimeTest : MonoBehaviour
{
    public float secound = 10;

    IEnumerator Start() //将Start方法作为协同程序，则不必调用StartCoroutine
    {        
        while (secound > 0)
        {
            yield return new WaitForSeconds(1);
            secound--;
            Debug.Log(secound);
        }
    }
}

5. 线程

using System.Threading;
using UnityEngine;

public class TimeTest : MonoBehaviour
{
    public float secound = 10;

    void Start()
    {
        Thread thread = new Thread(Timing);
        thread.Start();
    }

    private void Timing()
    {
        while (secound > 0)
        {
            Thread.Sleep(1000);
            secound--;
            Debug.Log(secound);
        }
    }
}