secToHHMM(number: number) {
    debugger;
    let hours = Math.floor(number / 3600);
    let minutes = Math.floor((number - (hours * 3600)) / 60);
    let seconds = number - (hours * 3600) - (minutes * 60);
    let H, M, S;
    if (hours < 10) H = ("0" + hours);
    if (minutes < 10) M = ("0" + minutes);
    if (seconds < 10) S = ("0" + seconds);
    return (H || hours) + ':' + (M || minutes) + ':' + (S || seconds);
}

我认为这是目前为止最快的性能:

var t = 34236; // your seconds
var time = ('0'+Math.floor(t/3600) % 24).slice(-2)+':'+('0'+Math.floor(t/60)%60).slice(-2)+':'+('0' + t % 60).slice(-2)
//would output: 09:30:36

function secondsToTime(secs)
{
    var hours = Math.floor(secs / (60 * 60));

    var divisor_for_minutes = secs % (60 * 60);
    var minutes = Math.floor(divisor_for_minutes / 60);

    var divisor_for_seconds = divisor_for_minutes % 60;
    var seconds = Math.ceil(divisor_for_seconds);

    if(hours >= 12)
    {
     var m= 'pm' ;
     }
     else
     {
         var m='am'
     }
     if(hours-12 >0)
     {
            var hrs = hours-12;
     }
     else if(hours-12 <0)
     {
            var hrs = hours;
     }
    var obj = {
        "h": hrs,
        "m": minutes,
        "s": seconds,
        "a":m
    };


    return obj;
}
var d = new Date();
var n = d.getHours();
var hms = d.getHours()+':'+d.getMinutes()+':'+d.getSeconds();   // your input string
var a = hms.split(':'); // split it at the colons

// minutes are worth 60 seconds. Hours are worth 60 minutes.
var seconds = (+a[0]) * 60 * 60 + (+a[1]) * 60 + (+a[2]); 




console.log(seconds);
console.log(secondsToTime(seconds))

https://jsfiddle.net/jithinksoft/9x6z4sdt/

要获得格式为hh:MM:ss的时间部分，可以使用下面的正则表达式:

(上面有人在同一篇文章中提到了这一点，谢谢。)

var替换= new日期().toTimeString () .replace (/ . * (\ d {2}: \ d {2}: \ d{2})。* / " $ 1 "); console.log(替换)

function formatTime(seconds) {
    return [
        parseInt(seconds / 60 / 60),
        parseInt(seconds / 60 % 60),
        parseInt(seconds % 60)
    ]
        .join(":")
        .replace(/\b(\d)\b/g, "0$1")
}

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;
}