查看“︁微件:Countdown”︁的源代码

<includeonly>
<!--{assign var="targetTime" value=$time|default:$t}-->
<span class="custom-countdown" 
      data-target="<!--{$targetTime|escape:'quotes'}-->" 
      data-before="<!--{$before|default:'$1前'|escape:'quotes'}-->" 
      data-after="<!--{$after|default:'还剩$1'|escape:'quotes'}-->">...</span>

<script>
(function() {
    let timer = null;
    function update() {
        const now = new Date();
        document.querySelectorAll('.custom-countdown').forEach(el => {
            let targetStr = el.getAttribute('data-target');
            const beforeTpl = el.getAttribute('data-before');
            const afterTpl = el.getAttribute('data-after');

            if (!targetStr) return;
            if (/^\d{4}$/.test(targetStr)) {
                targetStr += "-01-01T00:00:00";
            }
            if (/[+-]\d{2}$/.test(targetStr)) {
                targetStr += ":00";
            }
            if (/T\d{2}([+-]|Z|$)/.test(targetStr)) {
                targetStr = targetStr.replace(/(T\d{2})/, "$1:00:00");
            }

            const target = new Date(targetStr);
            if (isNaN(target)) {
                el.innerHTML = '<span style="color:red">时间格式错误 (' + targetStr + ')</span>';
                return;
            }

            const diff = target - now;
            const absDiff = Math.abs(diff);
            
            const days = Math.floor(absDiff / 864e5);
            const hours = Math.floor((absDiff % 864e5) / 36e5);
            const mins = Math.floor((absDiff % 36e5) / 6e4);
            const secs = Math.floor((absDiff % 6e4) / 1000);

            let diffStr = "";
            if (days > 0) diffStr += days + "天";
            if (hours > 0 || days > 0) diffStr += hours + "小时";
            if (mins > 0 || hours > 0 || days > 0) diffStr += mins + "分";
            diffStr += secs + "秒";

            if (diff > 0) {
                el.innerHTML = afterTpl.replace('$1', diffStr);
            } else {
                el.innerHTML = beforeTpl.replace('$1', diffStr);
            }
        });
    }

    function start() { if(!timer){ update(); timer=setInterval(update, 1000); } }
    function stop() { clearInterval(timer); timer=null; }
    document.addEventListener('visibilitychange', () => { document.hidden ? stop() : start(); });
    start();
})();
</script>
</includeonly><noinclude>
这是一个倒计时微件，仅供{{tl|Countdown}}使用。
</noinclude>