倒数HH:MM:SS在Jquery

Question

我想要倒数计时器的格式,hh:mm:ss所以我使用这个代码它将秒转换成所需的格式,但当我倒计时它显示我NaN.你能告诉我我做错了吗这是代码

<div id="timer"></div>

JS

String.prototype.toHHMMSS = function () {
    var sec_num = parseInt(this, 10); // don't forget the second parm
    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;
}

var count = '62';
count = count.toHHMMSS();

var counter = setInterval(timer, 1000);

function timer() {

    count--;
    if (count <= 0) {
        clearInterval(counter);
        return;
    }

    $('#timer').html(count);
}

这是JsFiddle链接CountDown Timer

Answer 1

好吧,让我们来看看你的代码做了什么:

• 设置count为字符串值62.
• 将其转换为HHMMSS,现在count等于字符串00:01:02
• 启动计时器.
• 在计时器的第一次运行时,减量count.嗯... count是一个字符串,你不能减少它.结果不是数字.

好的,那么就这样,修复它的方法:

function formatTime(seconds) {
    var h = Math.floor(seconds / 3600),
        m = Math.floor(seconds / 60) % 60,
        s = seconds % 60;
    if (h < 10) h = "0" + h;
    if (m < 10) m = "0" + m;
    if (s < 10) s = "0" + s;
    return h + ":" + m + ":" + s;
}
var count = 62;
var counter = setInterval(timer, 1000);

function timer() {
    count--;
    if (count < 0) return clearInterval(counter);
    document.getElementById('timer').innerHTML = formatTime(count);
}