说明： 方法1， 方法二是基础原理版，方法三升级版（参考for循环，定时器，闭包混合一块的那点事。）
方法一：
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>倒计时</title> </head> <body> <div></div> <div></div> </body> <script> function countDown( maxtime,fn ) { var timer = setInterval(function() { if( !!maxtime ){ var day = Math.floor(maxtime / 86400), hour = Math.floor((maxtime % 86400) / 3600), minutes = Math.floor((maxtime % 3600) / 60), seconds = Math.floor(maxtime%60), msg = "距离结束还有"+day+"天"+hour+"时"+minutes+"分"+seconds+"秒"; fn( msg ); --maxtime; } else { clearInterval( timer ); fn("时间到，结束!"); } }, 1000); } countDown( 86,function( msg ) { document.getElementById('timer1').innerHTML = msg; }) countDown( 86400,function( msg ) { document.getElementById('timer2').innerHTML = msg; }) </script> </html>
方法二：
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>倒计时</title> </head> <body> <div></div> <div></div> <div></div> </body> <script type="text/javascript"> var addTimer = function () { var list = [], interval; return function (id, time) { if (!interval) interval = setInterval(go, 1000); list.push({ ele: document.getElementById(id), time: time }); } function go() { for (var i = 0; i < list.length; i++) { list[i].ele.innerHTML = getTimerString(list[i].time ? list[i].time -= 1 : 0); if (!list[i].time) list.splice(i--, 1); } } function getTimerString(time) { var not0 = !!time, d = Math.floor(time / 86400), h = Math.floor((time %= 86400) / 3600), m = Math.floor((time %= 3600) / 60), s = time % 60; if (not0) return "还有" + d + "天" + h + "小时" + m + "分" + s + "秒"; else return "时间到"; } } (); addTimer("timer1", 12); addTimer("timer2", 10); addTimer("timer3", 13); </script> </html>
方法三：
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>倒计时</title> </head> <body> <div></div> <div></div> <div></div> </body> <script> function countDown( maxtime,fn ) { var timer = setInterval(function() { if( !!maxtime ){ var day = Math.floor(maxtime / 86400), hour = Math.floor((maxtime % 86400) / 3600), minutes = Math.floor((maxtime % 3600) / 60), seconds = Math.floor(maxtime%60), msg = "距离结束还有"+day+"天"+hour+"时"+minutes+"分"+seconds+"秒"; fn( msg ); --maxtime; } else { clearInterval( timer ); fn("时间到，结束!"); } }, 1000); } var aTime = [3600,3800,3900]; for ( var i = 0; i < 3; i++ ) { (function (i) { var obj = 'timer' + i; countDown( aTime[i],function( msg ) { document.getElementById(obj).innerHTML = msg; }) })(i) } </script> </html>