window.onload = startclock;
var timerID = null;  
var timerRunning = false;  
function stopclock (){  
 if(timerRunning)  
 clearTimeout(timerID);  
 timerRunning = false;}  
 function startclock () {  
 stopclock();  
 showtime();}  
 function showtime () {  
 var now = new Date();
 var weekDayLabels = new Array("星期日","星期一","星期二","星期三","星期四","星期五","星期六");
 var now = new Date();
 var year=now.getFullYear();
 var month=now.getMonth()+1;
 var day=now.getDate();
 var hour = now.getHours();  
 var minute = now.getMinutes();  
 var second = now.getSeconds();
 var timeValue = year+"年"+month+"月"+day+"日 "+weekDayLabels[now.getDay()]+" "+hour+"点"+minute+"分"+second+"秒";
 document.getElementById("clock").value = timeValue;
 timerID = setTimeout("showtime()",1000);  
 }