// set up
let start = moment("2018-05-16 12:00:00"); // some random moment in time (in ms)
let end = moment("2018-05-16 12:22:00"); // some random moment after start (in ms)
let diff = end.diff(start);

// execution
let f = moment.utc(diff.asMilliseconds()).format("HH:mm:ss.SSS");
alert(f);

看看JSFiddle

var diff = moment(end).unix() - moment(start).unix();
moment.utc(moment.duration(diff).asMilliseconds()).format("HH:mm:ss.SSS");

根据ni-ko-o-kin的回答:

meassurements = ["years", "months", "weeks", "days", "hours", "minutes", "seconds"];
withPadding = (duration) => {
    var step = null;
    return meassurements.map((m) => duration[m]()).filter((n,i,a) => {
        var nonEmpty = Boolean(n);
        if (nonEmpty || step || i >= a.length - 2) {
            step = true;
        }
        return step;
    }).map((n) => ('0' + n).slice(-2)).join(':')
}

duration1 = moment.duration(1, 'seconds');
duration2 = moment.duration(7200, 'seconds');
duration3 = moment.duration(604800, 'seconds');

withPadding(duration1); // 00:01
withPadding(duration2); // 02:00:00
withPadding(duration3); // 01:07:00:00:00

我使用:

var duration = moment.duration("09:30");
var str = moment(duration._data).format("HH:mm");

我在var str中得到"09:30"

如果你愿意使用不同的javascript库，numeric .js可以将秒格式化如下(例如1000秒):

var string = numeral(1000).format('00:00');
// '00:16:40'

import * as moment from 'moment'
var sleep = require('sleep-promise');

(async function () {
    var t1 = new Date().getTime();
    await sleep(1000); 
    var t2 = new Date().getTime();
    var dur = moment.duration(t2-t1); 
    console.log(`${dur.hours()}h:${dur.minutes()}m:${dur.seconds()}s`);
})();

0h:0m:1s