Javascript-倒数计时器

Question

我有此JS代码的倒计时功能。目前，它的计数是1分钟= 60秒。我需要的是计数60秒后显示在“ COUNTING FINISHED！”页面上。这是我的代码：

<h1>Countdown Clock</h1>
<div id="clockdiv">
  <div>
    <span class="days"></span>
    <div class="smalltext">Days</div>
  </div>
  <div>
    <span class="hours"></span>
    <div class="smalltext">Hours</div>
  </div>
  <div>
    <span class="minutes"></span>
    <div class="smalltext">Minutes</div>
  </div>
  <div>
    <span class="seconds"></span>
    <div class="smalltext">Seconds</div>
  </div>
</div>

和脚本：

function getTimeRemaining(endtime) {
  var t = Date.parse(endtime) - Date.parse(new Date());
  var seconds = Math.floor((t / 1000) % 60);
  var minutes = Math.floor((t / 1000 / 60) % 60);
  var hours = Math.floor((t / (1000 * 60 * 60)) % 24);
  var days = Math.floor(t / (1000 * 60 * 60 * 24));
  return {
    'total': t,
    'days': days,
    'hours': hours,
    'minutes': minutes,
    'seconds': seconds
  };
}

function initializeClock(id, endtime) {
  var clock = document.getElementById(id);
  var daysSpan = clock.querySelector('.days');
  var hoursSpan = clock.querySelector('.hours');
  var minutesSpan = clock.querySelector('.minutes');
  var secondsSpan = clock.querySelector('.seconds');

  function updateClock() {
    var t = getTimeRemaining(endtime);

    daysSpan.innerHTML = t.days;
    hoursSpan.innerHTML = ('0' + t.hours).slice(-2);
    minutesSpan.innerHTML = ('0' + t.minutes).slice(-2);
    secondsSpan.innerHTML = ('0' + t.seconds).slice(-2);

    if (t.total <= 0) {
      clearInterval(timeinterval);
    }
  }

  updateClock();
  var timeinterval = setInterval(updateClock, 1000);
}

var deadline = new Date(Date.parse(new Date()) + 60 * 1000);
initializeClock('clockdiv', deadline);

[最后一个</div>之后，我需要输入文字“ COUNTING FINISHED！”。计数结束后。用if statement有什么办法吗？请帮助！

Answer 1

如果您想在不阻塞页面的情况下睡眠，则可以创建一个异步函数

异步函数counter（）{

等待睡眠（60000）;document.getElementById（“ test”）。innerHTML =“您的代码”

}

Answer 2

[当我需要在特定时刻发生事情时，我倾向于（取决于我当时所用的语言）传递一个诺言或回调……以使事情变得容易，为什么不简单地通过回调？

function initializeClock(id, endtime, cbTimeEnded) { 

    ...

    if(t.total === 0) {
        clearInterval(timeinterval);
        if(cbTimeEnded) cbTimeEnded(); // only call the callback if exists
    }
}

然后

...
initializeClock('clockdiv', deadline, function() {
    // time reached the end, you can do whatever you want...
    console.log('done');
});