js倒计时 毫秒

// 设置倒计时的结束时间
let endTime = new Date(new Date().getTime() + 10 * 60 * 1000); // 当前时间加上10分钟

function updateCountdown() {
    let now = new Date().getTime();
    let distance = endTime - now;

    if (distance < 0) {
        clearInterval(interval);
        document.getElementById("countdown").innerHTML = "倒计时结束";
        return;
    }

    let minutes = Math.floor((distance % (1000 * 60 * 60)) / (1000 * 60));
    let seconds = Math.floor((distance % (1000 * 60)) / 1000);
    let milliseconds = Math.floor(distance % 1000);

    document.getElementById("countdown").innerHTML = 
        minutes + "分 " + seconds + "秒 " + milliseconds + "毫秒 ";
}

// 每隔10毫秒更新一次倒计时显示
let interval = setInterval(updateCountdown, 10);