js实现倒计时时钟的示例代码_javascript技巧

if (document.all||document.getElementById)
document.write('')

window.onload=start_countdown

function countdown(){
var today=new Date()
var todayy=today.getYear()
if (todayy todayy+=1900
var todaym=today.getMonth()
var todayd=today.getDate()
var todayh=today.getHours()
var todaymin=today.getMinutes()
var todaysec=today.getSeconds()
var todaystring=montharray[todaym]+" "+todayd+", "+todayy+" "+todayh+":"+todaymin+":"+todaysec
futurestring=montharray[mo-1]+" "+da+", "+yr
dd=Date.parse(futurestring)-Date.parse(todaystring)
dday=Math.floor(dd/(60*60*1000*24)*1)
dhour=Math.floor((dd%(60*60*1000*24))/(60*60*1000)*1)
dmin=Math.floor(((dd%(60*60*1000*24))%(60*60*1000))/(60*1000)*1)
dsec=Math.floor((((dd%(60*60*1000*24))%(60*60*1000))%(60*1000))/1000*1)
if(ddayif (document.layers){
document.countdownnsmain.document.countdownnssub.document.write(opentags+message_on_occasion+closetags)
document.countdownnsmain.document.countdownnssub.document.close()
}
else if (document.all||document.getElementById)
crosscount.innerHTML=opentags+message_on_occasion+closetags
return
}
else if (ddayif (document.layers){
document.countdownnsmain.document.countdownnssub.document.write(opentags+"时间已经过了!"+closetags)
document.countdownnsmain.document.countdownnssub.document.close()
}
else if (document.all||document.getElementById)
crosscount.innerHTML=opentags+"Occasion already passed! "+closetags
return
}
else{
if (document.layers){
document.countdownnsmain.document.countdownnssub.document.write(opentags+dday+ " days, "+dhour+" hours, "+dmin+" minutes, and "+dsec+" seconds left until "+occasion+closetags)
document.countdownnsmain.document.countdownnssub.document.close()
}
else if (document.all||document.getElementById)
crosscount.innerHTML=opentags+"还有 "+dday+ " 天, "+dhour+" 小时, "+dmin+" 分, "+dsec+" 秒 就是 "+occasion+closetags
}
setTimeout("countdown()",1000)
}

height="&{countdownheight};" width="&{countdownwidth};">id=countdownnssub height="&{countdownheight};"
width="&{countdownwidth};" top="0" left="0">