<html> <head> <script type="text/javascript"> function startTime() { var today=new Date() var h=today.getHours() var m=today.getMinutes() var s=today.getSeconds() // add a zero in front of numbers<10 m=checkTime(m) s=checkTime(s) document.getElementById(‘txt‘).innerHTML=h+":"+m+":"+s t=setTimeout(‘startTime()‘,500) } function checkTime(i) { if (i<10) {i="0" + i} return i } </script> </head> <body onload="startTime()"> <div id="txt"></div> </body> </html>
原文：http://www.cnblogs.com/eric-qin/p/4056136.html