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;
    }   

以下是@meiyang的优秀解决方案的一个变体，我最终使用了它:

    function duration(seconds) {
        return [
            format(seconds / 60 / 60),
            format(seconds / 60 % 60),
            format(seconds % 60)
        ].join(':');
    }

    format(n) {
        return (~~n).toString().padStart(2, '0')
    }

PS:同样值得注意的是，上面的一些其他解决方案只适用于< 24h的值

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;
}

你现在可以这样使用它:

alert("5678".toHHMMSS());

工作代码片段:

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; } console.log("5678".toHHMMSS());

你可以在没有任何外部JS库的帮助下使用JS Date方法做到这一点，如下所示:

var date = new date (0); date.setSeconds (45);//指定SECONDS的值 var timeString = date.toISOString()。substring(11、19); console.log (timeString)

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"

我个人更喜欢不带前导零的开头单位(天、小时、分钟)。但是秒应该总是以分钟(0:13)开头，这种表示很容易被认为是“持续时间”，不需要进一步解释(标记为min, sec(s)等)，可用于各种语言(国际化)。

    // returns  (-)d.h:mm:ss(.f)
    //          (-)h:mm:ss(.f)
    //          (-)m:ss(.f)
    function formatSeconds (value, fracDigits) {
        var isNegative = false;
        if (isNaN(value)) {
            return value;
        } else if (value < 0) {
            isNegative = true;
            value = Math.abs(value);
        }
        var days = Math.floor(value / 86400);
        value %= 86400;
        var hours = Math.floor(value / 3600);
        value %= 3600;
        var minutes = Math.floor(value / 60);
        var seconds = (value % 60).toFixed(fracDigits || 0);
        if (seconds < 10) {
            seconds = '0' + seconds;
        }

        var res = hours ? (hours + ':' + ('0' + minutes).slice(-2) + ':' + seconds) : (minutes + ':' + seconds);
        if (days) {
            res = days + '.' + res;
        }
        return (isNegative ? ('-' + res) : res);
    }

//模仿服务器端(.net, c#)持续时间格式:

    public static string Format(this TimeSpan interval)
    {
        string pattern;
        if (interval.Days > 0)          pattern = @"d\.h\:mm\:ss";
        else if (interval.Hours > 0)    pattern = @"h\:mm\:ss";
        else                            pattern = @"m\:ss";
        return string.Format("{0}", interval.ToString(pattern));
    }