有明确结束时间的倒计时
<body>
<div id="hxtime" style="padding:5px 0 0 0;"></div>
<script language="JavaScript">
var hxtime=document.getElementById("hxtime");
var timer=null;
//console.log(hxtime);
function ShowTimes(){
var endtime=new Date("2017/10/19 11:32:00");
var nowtime=new Date();
var LeaveTime=endtime-nowtime;
//Math.floor向下取整
var LeaveDays=Math.floor(LeaveTime/(1000*60*60*24))//天
var LeaveHours=Math.floor(LeaveTime/(1000*60*60)%24);//小时
var LeaveMinutes=Math.floor(LeaveTime/(1000*60)%60);//分
var LeaveSeconds=Math.floor(LeaveTime/(1000)%60);//秒
if(LeaveTime<0){
hxtime.innerHTML="抢购已结束";
clearInterval(timer);
}else{
hxtime.innerHTML="距离相见的日子还有<font color=red>" + LeaveDays + "</font>天<font color=red>" + LeaveHours + "</font>时<font color=red>" + LeaveMinutes + "</font>分<font color=red>" + LeaveSeconds + "</font>秒<font color=red>";
}
}
timer=setInterval(ShowTimes,1000);
</script>
</body>
点击发送验证码60秒倒计时
<body>
<input type="text" id="txt">
<button id="btn">点击发送短信验证码</button>
<script language="JavaScript">
var btn=document.getElementById('btn');
var countdown=60;
var timer=null;
btn.onclick=settime;
function settime(){
if(countdown==0){
clearTimeout(timer)
btn.removeAttribute("disabled");
btn.innerHTML="免费获取验证码";
countdown=60;
return;
}else{
btn.setAttribute("disabled",true);
btn.innerHTML="重新发送("+countdown+")";
countdown--;
}
timer=setTimeout(function() {
settime()
},1000)
}
</script>
</body>
5秒倒计时跳转页面
<body>
<div id="btn">欢迎</div>
<script language="JavaScript">
var countdown=5;
var btn=document.getElementById("btn")
var timer=null;
setTime();
function setTime(){
if(countdown==0){
clearTimeout(timer);
window.location="http://www.baidu.com";
}else{
btn.innerHTML="倒计时"+countdown+"s";
countdown--;
}
setTimeout(function(){
setTime()
},1000);
}
</script>
</body>