这招很管用:

function secondstotime(secs)
{
    var t = new Date(1970,0,1);
    t.setSeconds(secs);
    var s = t.toTimeString().substr(0,8);
    if(secs > 86399)
        s = Math.floor((t - Date.parse("1/1/70")) / 3600000) + s.substr(2);
    return s;
}

(来源此处)

我知道这有点老了，但是…

ES2015:

var toHHMMSS = (secs) => {
    var sec_num = parseInt(secs, 10)
    var hours   = Math.floor(sec_num / 3600)
    var minutes = Math.floor(sec_num / 60) % 60
    var seconds = sec_num % 60

    return [hours,minutes,seconds]
        .map(v => v < 10 ? "0" + v : v)
        .filter((v,i) => v !== "00" || i > 0)
        .join(":")
}

它将输出:

toHHMMSS(129600) // 36:00:00
toHHMMSS(13545) // 03:45:45
toHHMMSS(180) // 03:00
toHHMMSS(18) // 00:18

这里有一个转换时间的简单函数，可能会有帮助

function formatSeconds(seconds) {
    var date = new Date(1970,0,1);
    date.setSeconds(seconds);
    return date.toTimeString().replace(/.*(\d{2}:\d{2}:\d{2}).*/, "$1");
}

String.prototype.toHHMMSS = function () {
    var sec_num = parseInt(this, 10); // don't forget the second param
    var hours   = Math.floor(sec_num / 3600);
    var minutes = Math.floor((sec_num - (hours * 3600)) / 60);
    var seconds = sec_num - (hours * 3600) - (minutes * 60);

    if (hours   < 10) {hours   = "0"+hours;}
    if (minutes < 10) {minutes = "0"+minutes;}
    if (seconds < 10) {seconds = "0"+seconds;}
    return hours+':'+minutes+':'+seconds;
}

使用的例子

alert("186".toHHMMSS());

var sec_to_hms = function(sec){
var min, hours;
     sec = sec - (min = Math.floor(sec/60))*60;
     min = min - (hours = Math.floor(min/60))*60;
     return (hours?hours+':':'') + ((min+'').padStart(2, '0')) + ':'+ ((sec+'').padStart(2, '0'));
}
alert(sec_to_hms(2442542));

这是一个非常简单的任务，但你们中的一些人直接推荐了Moment.js，或者创建了一些最丑陋的函数来解析一些秒…

transform(time: number): string {
    if (time != null) {
        const hours: number = Math.floor(time / 3600);
        const minutes: number = Math.floor((time - (hours * 3600)) / 60);
        const seconds: number = time - (hours * 3600) - (minutes * 60);
        return [hours, (minutes < 10) ? '0' + minutes : minutes, (seconds < 10) ? '0' + seconds : seconds].join(':');
    } else {
        return '00:00:00';
    }
}

这在任何情况下都适用……