我只是想对上面这个不错的答案做一点解释:

var totalSec = new Date().getTime() / 1000;
var hours = parseInt( totalSec / 3600 ) % 24;
var minutes = parseInt( totalSec / 60 ) % 60;
var seconds = totalSec % 60;

var result = (hours < 10 ? "0" + hours : hours) + "-" + (minutes < 10 ? "0" + minutes : minutes) + "-" + (seconds  < 10 ? "0" + seconds : seconds);

On the second line, since there are 3600 seconds in 1 hour, we divide the total number of seconds by 3600 to get the total number of hours. We use parseInt to strip off any decimal. If totalSec was 12600 (3 and half hours), then parseInt( totalSec / 3600 ) would return 3, since we will have 3 full hours. Why do we need the % 24 in this case? If we exceed 24 hours, let's say we have 25 hours (90000 seconds), then the modulo here will take us back to 1 again, rather than returning 25. It is confining the result within a 24 hour limit, since there are 24 hours in one day.

当你看到这样的东西:

25 % 24

你可以这样想:

25 mod 24 or what is the remainder when we divide 25 by 24

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)

下面是一个函数，根据powtac的答案将秒转换为hh-mm-ss格式

斯菲德尔

/** 
 * Convert seconds to hh-mm-ss format.
 * @param {number} totalSeconds - the total seconds to convert to hh- mm-ss
**/
var SecondsTohhmmss = function(totalSeconds) {
  var hours   = Math.floor(totalSeconds / 3600);
  var minutes = Math.floor((totalSeconds - (hours * 3600)) / 60);
  var seconds = totalSeconds - (hours * 3600) - (minutes * 60);

  // round seconds
  seconds = Math.round(seconds * 100) / 100

  var result = (hours < 10 ? "0" + hours : hours);
      result += "-" + (minutes < 10 ? "0" + minutes : minutes);
      result += "-" + (seconds  < 10 ? "0" + seconds : seconds);
  return result;
}

示例使用

var seconds = SecondsTohhmmss(70);
console.log(seconds);
// logs 00-01-10

对于HH:MM:SS的特殊情况。MS (eq: "00:04:33.637")， FFMPEG用来指定毫秒。

[-] [HH: MM: SS(打烊……) HH表示小时数，MM表示分钟数 最大值为2位，SS为最大值为2的秒数 位数。最后的m表示SS的十进制值。

/* HH:MM:SS.MS to (FLOAT)seconds ---------------*/ function timerToSec(timer){ let vtimer = timer.split(":") let vhours = +vtimer[0] let vminutes = +vtimer[1] let vseconds = parseFloat(vtimer[2]) return vhours * 3600 + vminutes * 60 + vseconds } /* Seconds to (STRING)HH:MM:SS.MS --------------*/ function secToTimer(sec){ let o = new Date(0) let p = new Date(sec*1000) return new Date(p.getTime()-o.getTime()) .toISOString() .split("T")[1] .split("Z")[0] } /* Example: 7hours, 4 minutes, 33 seconds and 637 milliseconds */ const t = "07:04:33.637" console.log( t + " => " + timerToSec(t) + "s" ) /* Test: 25473 seconds and 637 milliseconds */ const s = 25473.637 // "25473.637" console.log( s + "s => " + secToTimer(s) )

示例使用，毫秒传输计时器:

/* Seconds to (STRING)HH:MM:SS.MS --------------*/ function secToTimer(sec){ let o = new Date(0) let p = new Date(sec*1000) return new Date(p.getTime()-o.getTime()) .toISOString() .split("T")[1] .split("Z")[0] } let job, origin = new Date().getTime() const timer = () => { job = requestAnimationFrame(timer) OUT.textContent = secToTimer((new Date().getTime() - origin) / 1000) } requestAnimationFrame(timer) span {font-size:4rem} <span id="OUT"></span> <br> <button onclick="origin = new Date().getTime()">RESET</button> <button onclick="requestAnimationFrame(timer)">RESTART</button> <button onclick="cancelAnimationFrame(job)">STOP</button>

绑定到媒体元素的示例用法

/* Seconds to (STRING)HH:MM:SS.MS --------------*/ function secToTimer(sec){ let o = new Date(0) let p = new Date(sec*1000) return new Date(p.getTime()-o.getTime()) .toISOString() .split("T")[1] .split("Z")[0] } VIDEO.addEventListener("timeupdate", function(e){ OUT.textContent = secToTimer(e.target.currentTime) }, false) span {font-size:4rem} <span id="OUT"></span><br> <video id="VIDEO" width="400" controls autoplay> <source src="https://www.w3schools.com/html/mov_bbb.mp4" type="video/mp4"> </video>

在问题之外，那些用php编写的函数:

<?php 
/* HH:MM:SS to (FLOAT)seconds ------------------*/
function timerToSec($timer){
  $vtimer = explode(":",$timer);
  $vhours = (int)$vtimer[0];
  $vminutes = (int)$vtimer[1];
  $vseconds = (float)$vtimer[2];
  return $vhours * 3600 + $vminutes * 60 + $vseconds;
}
/* Seconds to (STRING)HH:MM:SS -----------------*/
function secToTimer($sec){
  return explode(" ", date("H:i:s", $sec))[0];  
}

export const secondsToHHMMSS = (seconds) => {
  const HH = `${Math.floor(seconds / 3600)}`.padStart(2, '0');
  const MM = `${Math.floor(seconds / 60) % 60}`.padStart(2, '0');
  const SS = `${Math.floor(seconds % 60)}`.padStart(2, '0');
  return [HH, MM, SS].join(':');
};

当我想象一个时钟或计时器时，我会这样做:

const secondsTo_HHMMSS = (seconds) => {
      //format to a readable friendly timer
      let hour = Math.floor(seconds / 3600);
      let minute = Math.floor((seconds % 3600) / 60);
      let second = seconds % 60;

      if(hour.toString().length === 1) {
            hour = `0${hour}`;
      }
      if(minute.toString().length === 1) {
            minute = `0${minute}`;
      }
      if(second.toString().length === 1) {
            second = `0${second}`;
      };

      let timer = `${hour}-${minute}-${second}`;

      return timer;
}