js实现倒计时时钟的示例代码

  如下所示:

  

复制代码 代码如下:

  <!--将以下代码加入HTML的<Body></Body>之间-->

  <SCRIPT language=JavaScript1.2>

  function setcountdown(theyear,themonth,theday){

  yr=theyear;mo=themonth;da=theday

  }

  setcountdown(2008,7,12)

  var occasion="2008北京奥运会"

  var message_on_occasion="盼望已久的时刻终于来到了!"

  var countdownwidth='480px'

  var countdownheight='20px'

  var countdownbgcolor='tan'

  var opentags='<font face="宋体"><small>'

  var closetags='</small></font>'

  var montharray=new Array("Jan","Feb","Mar","Apr","May","Jun","Jul","Aug","Sep","Oct","Nov","Dec")

  var crosscount=''

  function start_countdown(){

  if (document.layers)

  document.countdownnsmain.visibility="show"

  else if (document.all||document.getElementById)

  crosscount=document.getElementById&&!document.all?document.getElementById("countdownie") : countdownie

  countdown()

  }

  if (document.all||document.getElementById)

  document.write('<span id="countdownie" style="width:'+countdownwidth+'; background-color:'+countdownbgcolor+'"></span>')

  window.onload=start_countdown

  function countdown(){

  var today=new Date()

  var todayy=today.getYear()

  if (todayy < 1000)

  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(dday<=0&&dhour<=0&&dmin<=0&&dsec<=1&&todayd==da){

  if (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 (dday<=-1){

  if (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)

  }

  </SCRIPT>

  <SCRIPT type="text/javascript" src=""></SCRIPT>

  <SCRIPT language="JavaScript">

  <!--

  BaiduWriteAD("zouwenyedg","3");

  //-->

  </SCRIPT>

  <ILAYER id=countdownnsmain visibility="hide" bgColor="&{countdownbgcolor};"

  height="&{countdownheight};" width="&{countdownwidth};"><LAYER

  id=countdownnssub height="&{countdownheight};"

  width="&{countdownwidth};" top="0" left="0"></LAYER></ILAYER>