javascript - 关于JS倒计时的问题
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问题描述
问 题
倒计时的秒数显示不正常。太慢。点解。。。
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
</head>
<body>
<h2>毫秒的倒计时</h2>
<div id="timer2"></div>
<script>
var countdown = function(gid,time){
try {
if (time<=0) {
} else {
var ms = Math.floor(time%1000);
var s = Math.floor(time/1000%60);
var m = Math.floor(time/1000/60%60);
var h =Math.floor(time/1000/60/60%24);
h=h>9?h:'0'+h;
m=m>9?m:'0'+m;
s=s>9?s:'0'+s;
ms=ms>9?ms:'0'+ms;
if (parseInt(h)>0) {
var str = h+':'+m+':'+s;
} else {
var str = m+':'+s+':'+ms;
}
document.getElementById('timer2').innerHTML = str;
setTimeout(function(){
countdown(gid,time-1);
},1);
}
} catch (e) {
if (typeof(console) == 'object') {
console.log(e);
}
}
};
setTimeout(function(){countdown('timer2',99999)},1);
</script>
</body>
</html>
在线测试：https://jsfiddle.net/L6qvefu3/
解决方案
@Hello_World20 说的就是正确的，js里要准确计时只能用Date的时间戳
按题主的代码改了下，应该就是题主想要的效果了
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
</head>
<body>
<h2>毫秒的倒计时</h2>
<div id="timer2"></div>
<script>
var countdown = function(gid,time,starttime){
if (!starttime) starttime = Date.now();
try {
var _time = time + starttime - Date.now();
if (_time<=0) {
document.getElementById('timer2').innerHTML = '00:00:00';
} else {
var ms = Math.floor(_time%1000);
var s = Math.floor(_time/1000%60);
var m = Math.floor(_time/1000/60%60);
var h = Math.floor(_time/1000/60/60%24);
h=h>9?h:'0'+h;
m=m>9?m:'0'+m;
s=s>9?s:'0'+s;
ms=ms>9?ms:'0'+ms;
if (parseInt(h)>0) {
var str = h+':'+m+':'+s;
} else {
var str = m+':'+s+':'+ms;
}
document.getElementById('timer2').innerHTML = str;
setTimeout(function(){
countdown(gid, time, starttime);
},1);
}
} catch (e) {
if (typeof(console) == 'object') {
console.log(e);
}
}
};
setTimeout(function(){countdown('timer2',99999)},1);
</script>
</body>
</html>这篇关于javascript - 关于JS倒计时的问题的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
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