<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title></title>
<script>
var i=0;//总秒数
var timer=null;
window.onload=function(){
document.getElementById("start").onclick=function(){
timer=setInterval(function(){
i++;
document.getElementById("sec").innerHTML=doubleNum(i%60);
document.getElementById("min").innerHTML=doubleNum(parseInt(i/60)%60);
document.getElementById("hour").innerHTML=doubleNum(parseInt(i/3600));
},1000);
}
document.getElementById("pause").onclick=function(){
clearInterval(timer);
}
document.getElementById("reast").onclick=function(){
clearInterval(timer);
i=0;
document.getElementById("sec").innerHTML="00";
document.getElementById("min").innerHTML="00";
document.getElementById("hour").innerHTML="00";
}
}
function doubleNum(n){
if(n<10){
return "0"+n;
}else{
return n;
}
}
</script>
</head>
<body>
<div id="div1">
<span id ="hour">00</span>
<span>:</span>
<span id ="min">00</span>
<span>:</span>
<span id ="sec">00</span>
<br />
<hr />
<button id="start">开始</button>
<button id="pause">暂停</button>
<button id="reast">复位</button>
</div>
</body>
</html>