向倒数计时器添加开始按钮

Question

我在倒数计时器中添加了一个开始按钮，但是它不起作用。当我运行它时，它说启动未定义。我检查了代码，然后控制台打印出以下错误：“未捕获的ReferenceError：在HTMLButtonElement.onclick上未定义开始”。在上面的代码中，我添加了启动功能，它将启动我的倒数计时器。你能告诉我我在想什么吗？我看了其他示例，但仍然无法使其正常工作。

	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();

		function start(){
			var timeinterval = setInterval(updateClock, 1000);
		}
	}

	var deadline = new Date("Jan 5, 2021 15:37:25");

	//var deadline = new Date($scope.data.deadLine); //new Date(Date.parse(new Date()) + 15 * 24 * 60 * 60 * 1000);
	initializeClock('clockdiv', deadline);

body{
	text-align: center;
	background: #00ECB9;
  font-family: sans-serif;
  font-weight: 100;
}

h1{
  color: #396;
  font-weight: 100;
  font-size: 40px;
  margin: 40px 0px 20px;
}

#clockdiv{
	font-family: sans-serif;
	color: #fff;
	display: inline-block;
	font-weight: 100;
	text-align: center;
	font-size: 30px;
}

#clockdiv > div{
	padding: 10px;
	border-radius: 3px;
	background: #00BF96;
	display: inline-block;
}

#clockdiv div > span{
	padding: 15px;
	border-radius: 3px;
	background: #00816A;
	display: inline-block;
}

.smalltext{
	padding-top: 5px;
	font-size: 16px;
}

<div>
  <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>

</div>

<button type="button" onclick="start()">Start</button>
<button type="button" onclick="stop()">Stop</button>

Answer 1

如果要继续使用相同的代码，则可以在 initializeClock 函数中使用启动功能，如下所示，您必须对代码进行一些细微更改。

<div>
 <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>

开始 停止

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 timeinterval;
    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();

    this.start = function(){
        timeinterval = setInterval(updateClock, 1000);
    }
    this.stop = function(){
      clearInterval(timeinterval);
    }
}

var deadline = new Date("Jan 5, 2021 15:37:25");
var init = new initializeClock('clockdiv', deadline);
initializeClock('clockdiv', deadline);