可以使用以下函数将时间转换为HH:MM:SS格式:

var convertTime = function (input, separator) {
    var pad = function(input) {return input < 10 ? "0" + input : input;};
    return [
        pad(Math.floor(input / 3600)),
        pad(Math.floor(input % 3600 / 60)),
        pad(Math.floor(input % 60)),
    ].join(typeof separator !== 'undefined' ?  separator : ':' );
}

在不传递分隔符的情况下，它使用:作为(默认)分隔符:

time = convertTime(13551.9941351); // --> OUTPUT = 03:45:51

如果你想使用-作为分隔符，只需将其作为第二个参数传递:

time = convertTime(1126.5135155, '-'); // --> OUTPUT = 00-18-46

Demo

var convertTime = function (input, separator) { var pad = function(input) {return input < 10 ? "0" + input : input;}; return [ pad(Math.floor(input / 3600)), pad(Math.floor(input % 3600 / 60)), pad(Math.floor(input % 60)), ].join(typeof separator !== 'undefined' ? separator : ':' ); } document.body.innerHTML = '<pre>' + JSON.stringify({ 5.3515555 : convertTime(5.3515555), 126.2344452 : convertTime(126.2344452, '-'), 1156.1535548 : convertTime(1156.1535548, '.'), 9178.1351559 : convertTime(9178.1351559, ':'), 13555.3515135 : convertTime(13555.3515135, ',') }, null, '\t') + '</pre>';

看看这小提琴。

如果你知道你有多少秒，这就可以了。它还使用本机Date()对象。

function formattime(numberofseconds){    
    var zero = '0', hours, minutes, seconds, time;

    time = new Date(0, 0, 0, 0, 0, numberofseconds, 0);

    hh = time.getHours();
    mm = time.getMinutes();
    ss = time.getSeconds() 

    // Pad zero values to 00
    hh = (zero+hh).slice(-2);
    mm = (zero+mm).slice(-2);
    ss = (zero+ss).slice(-2);

    time = hh + ':' + mm + ':' + ss;
    return time; 
}

主题的变奏。处理个位数秒的方式有点不同

seconds2time(0)  ->  "0s" 
seconds2time(59) -> "59s" 
seconds2time(60) -> "1:00" 
seconds2time(1000) -> "16:40" 
seconds2time(4000) -> "1:06:40"

function seconds2time (seconds) {
    var hours   = Math.floor(seconds / 3600);
    var minutes = Math.floor((seconds - (hours * 3600)) / 60);
    var seconds = seconds - (hours * 3600) - (minutes * 60);
    var time = "";

    if (hours != 0) {
      time = hours+":";
    }
    if (minutes != 0 || time !== "") {
      minutes = (minutes < 10 && time !== "") ? "0"+minutes : String(minutes);
      time += minutes+":";
    }
    if (time === "") {
      time = seconds+"s";
    }
    else {
      time += (seconds < 10) ? "0"+seconds : String(seconds);
    }
    return time;
}

最普遍的答案是

function hms(seconds) {
  return [3600, 60]
    .reduceRight(
      (p, b) => r => [Math.floor(r / b)].concat(p(r % b)),
      r => [r]
    )(seconds)
    .map(a => a.toString().padStart(2, '0'))
    .join(':');
}

一些示例输出:

> hms(0)
< "00:00:00"

> hms(5)
< "00:00:05"

> hms(60)
< "00:01:00"

> hms(3785)
< "01:03:05"

> hms(37850)
< "10:30:50"

> hms(378500)
< "105:08:20"

详见https://stackoverflow.com/a/66504936/1310733

以下是2019年更新的一句话:

//your date
var someDate = new Date("Wed Jun 26 2019 09:38:02 GMT+0100") 

var result = `${String(someDate.getHours()).padStart(2,"0")}:${String(someDate.getMinutes()).padStart(2,"0")}:${String(someDate.getSeconds()).padStart(2,"0")}`

//result will be "09:38:02"

toHHMMSS的非原型版本:

    function toHHMMSS(seconds) {
        var sec_num = parseInt(seconds);
        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;}
        var time    = hours+':'+minutes+':'+seconds;
        return time;
    }