计时器在很多地方都有用,比如之前在写的答题页面中就有用到计时。
JS
t=setTimeout("timedCount()",1000);
setTimeout(“调用的函数”,以毫秒为单位的时间);
HTML
<form id="time-counter">
时间还有:
<input type="text" id="txt" value="0时0分0秒" readOnly="readonly"/>
</form>
js
正计时
var c=0;
var t;
function timedCount()
{
var temptextmin=document.getElementById('txt');
hour = parseInt(c / 3600);// 小时数
min = parseInt(c / 60);// 分钟数
if(min>=60){
min=min%60;
}
if(min<10)
min="0"+ min;
lastsecs = c % 60;
if(lastsecs<10)
lastsecs="0"+ lastsecs;
temptextmin.value = hour + "时" + min + "分" + lastsecs + "秒";
c=c+1;
t=setTimeout("timedCount()",1000);
}
倒计时
var t;
function timedCount() {
var temptextmin = document.getElementById('txt');
var now = new Date();//定义一个现在的时间
var SetEnd = new Date();//设置结束考试时间
SetEnd.setHours(22, 30, 00);//(时,分,秒)
var leftTime=SetEnd.getTime()-now.getTime();
var leftsecond = parseInt(leftTime/1000);
var hour=Math.floor(leftsecond/3600);
var minute=Math.floor((leftsecond-hour*3600)/60);
var second=Math.floor(leftsecond-hour*3600-minute*60);
if((hour==0)&(minute ==0)&(second == 0))
{//判断时间和考试开始时间是否一致
alert("考试结束,接下来将自动帮你提交试卷");
document.getElementById("myform").submit();
}
temptextmin.value = hour + "时" + minute + "分" + second + "秒";//在页面显示时间
t=setTimeout("timedCount()",1000);
}