在我的秒表（js）中添加ms单位并删除小时单位

Question

我尝试将ms单位添加到此秒表并删除小时单位。有人可以向我展示如何做到这一点的例子吗？ https://jsfiddle.net/pvk6p/

<h1><time>00:00:00</time></h1>

---

var h1 = document.getElementsByTagName('h1')[0],
    start = document.getElementById('start'),
    stop = document.getElementById('stop'),
    clear = document.getElementById('clear'),
    seconds = 0, minutes = 0, hours = 0,
    t;

function add() {
    seconds++;
    if (seconds >= 60) {
        seconds = 0;
        minutes++;
        if (minutes >= 60) {
            minutes = 0;
            hours++;
        }
    }

    h1.textContent =
        (hours ? (hours > 9 ? hours : "0" + hours) : "00" )
        + ":" + 
        (minutes ? (minutes > 9 ? minutes : "0" + minutes) : "00")
        + ":" +
        (seconds > 9 ? seconds : "0" + seconds);

    timer();
}
function timer() {
    t = setTimeout(add, 1000);
}
timer();

Answer 1

您可以尝试以下方法：

var h1 = document.getElementsByTagName('h1')[0],
    start = document.getElementById('start'),
    stop = document.getElementById('stop'),
    clear = document.getElementById('clear'),
    seconds = 0, minutes = 0, ms = 0,
    t;

function add() {
    ms++;
    if (ms >= 100) {
        ms = 0;
        seconds++;
        if (seconds >= 60) {
            seconds = 0;
            minutes++;
        }
    }

    h1.textContent = (minutes ? (minutes > 9 ? minutes : "0" + minutes) : "00") 
    + ":" + (seconds > 9 ? seconds : "0" + seconds)
    + ":" + (ms > 9 ? ms : "0" + ms);
   // + ":" + (ms > 99 ? ms : (ms > 9 ? "0"+ms : "00" + ms));
   //if you want to try to display every 1ms

    timer();
}
function timer() {
    t = setTimeout(add, 10);
}
timer();


/* Start button */
start.onclick = timer;

/* Stop button */
stop.onclick = function() {
    clearTimeout(t);
}

/* Clear button */
clear.onclick = function() {
    h1.textContent = "00:00:00";
    seconds = 0; minutes = 0; ms = 0;
}

jsfiddle：https://jsfiddle.net/pvk6p/5190/

如果您想尝试每1毫秒而不是10毫秒调用一次：

替换：  if (ms >= 100) {的{​​{1}}

if (ms >= 1000) {由+ ":" + (ms > 9 ? ms : "0" + ms);

+ ":" + (ms > 99 ? ms : (ms > 9 ? "0"+ms : "00" + ms));由t = setTimeout(add, 10);

但是在我的PC上，这很慢，而且要比1ms多一点。