Date 对象属性
<script> window.onload = function () { var t2 = document.getElementsByClassName('time2'); var er = t2[0].getElementsByTagName('div'); var t1 = document.getElementsByClassName('time1')[0]; var er2 = t1.getElementsByTagName('div'); function getnum(num) { if (num < 10) { return '0' + num; } else return '' + num; } var timer; var str, str1; function getStr() { var dat = new Date(); str = getnum(dat.getHours()) + getnum(dat.getMinutes()) + getnum(dat.getSeconds()); str1 = dat.getFullYear() + getnum(dat.getMonth() + 1) + getnum(dat.getDate()); for (var i = 0; i < str1.length; i++) er2[i].className = 'er' + str1[i]; for (var i = 0; i < str.length; i++) { er[i].className = ('er' + str[i]); } } var st = document.getElementsByClassName('stop'); timer = setInterval(getStr, 1000); st[0].onclick = function () { clearInterval(timer); } st[1].onclick = function () { getStr(); </script>