如何在jquery中自定义倒计时计时器

Question

我正在使用Jquery，我正在显示"倒计时计时器"使用jquery，现在我显示的是1分25秒的计时器但在此之后，我得到"-1分59秒"，应该有显示"0分0秒"，我怎么能做到这一点?这是我当前的代码

<script>
var timer2 = "0:25";
var interval = setInterval(function() {
var timer = timer2.split(':');
//by parsing integer, I avoid all extra string processing
var minutes = parseInt(timer[0], 10);
var seconds = parseInt(timer[1], 10);
--seconds;
minutes = (seconds < 0) ? --minutes : minutes;
if (minutes < 0) clearInterval(interval);
seconds = (seconds < 0) ? 59 : seconds;
seconds = (seconds < 10) ? '0' + seconds : seconds;
//minutes = (minutes < 10) ?  minutes : minutes;
$('.countdown').html(minutes + ' minutes : ' + seconds + ' seconds');
timer2 = minutes + ':' + seconds;
}, 1000);

</script>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div class="countdown"></div>

Answer 1

在屏幕上显示结果之前，您缺少return语句。

var timer2 = "0:5";
var interval = setInterval(function() {
var timer = timer2.split(':');
var minutes = parseInt(timer[0], 10);
var seconds = parseInt(timer[1], 10);
--seconds;
minutes = (seconds < 0) ? --minutes : minutes;
if (minutes < 0) {
clearInterval(interval);
return;                     /* ADD THIS */
}
seconds = (seconds < 0) ? 59 : seconds;
seconds = (seconds < 10) ? '0' + seconds : seconds;
//minutes = (minutes < 10) ?  minutes : minutes;
$('.countdown').html(minutes + ' minutes : ' + seconds + ' seconds');
timer2 = minutes + ':' + seconds;
}, 1000);

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div class="countdown"></div>

否则(没有return)确保您的seconds也在0

var timer2 = "0:5";
var interval = setInterval(function() {
var timer = timer2.split(':');
var minutes = parseInt(timer[0], 10);
var seconds = parseInt(timer[1], 10);
--seconds;
minutes = (seconds < 0) ? --minutes : minutes;
if (minutes === 0 && seconds === 0) clearInterval(interval);  /* EDIT */
seconds = (seconds < 0) ? 59 : seconds;
seconds = (seconds < 10) ? '0' + seconds : seconds;
//minutes = (minutes < 10) ?  minutes : minutes;
$('.countdown').html(minutes + ' minutes : ' + seconds + ' seconds');
timer2 = minutes + ':' + seconds;
}, 1000);

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div class="countdown"></div>