JavaScript 网页中实现一个计算当年还剩多少时间的倒数计时程序

function counter() {   var date = new Date();   var year = date.getFullYear();   var date2 = new Date(year, 11, 30, 23, 59, 59);   /*转换成秒*/   var time = (date2 - date) / 1000;   var day = Math.floor(time / (24 * 60 * 60))   var hour = Math.floor(time % (24 * 60 * 60) / (60 * 60))   var minute = Math.floor(time % (24 * 60 * 60) % (60 * 60) / 60);   var second = Math.floor(time % (24 * 60 * 60) % (60 * 60) % 60);   var str = year + "年还剩" + day + "天" + hour + "时" + minute + "分" + second + "秒";   console.log(str); } window.setInterval("counter()", 1000); 

var oDateNow = new Date();var oYear = oDateNow.getFullYear();var oDateEnd = new Date();oDateEnd.setFullYear(oYear+1);oDateEnd.setMonth(0);oDateEnd.setDate(0);oDateEnd.setHours(0);oDateEnd.setMinutes(0);oDateEnd.setSeconds(0);function upDate(){var oDateNow = new Date();var iTime = oDateEnd.getTime()-oDateNow.getTime();var iRemain = iTime/1000;var iDay=parseInt(iRemain/86400);iRemain%=86400;var iHour=parseInt(iRemain/3600);iRemain%=3600;var iMin=parseInt(iRemain/60);iRemain%=60;var iSec=parseInt(iRemain);document.write(oYear+"年还剩"+iDay+"天"+iHour+"时"+iMin+"分"+iSec+"秒");}setInterval(function(){ upDate() },1000);