JavaScript 动态时钟实现代码

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" <html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312" />
<title>动态时钟</title>
<script type="text/javascript">
//在网页上输出：今天的日期、星期、现在的时间（动态时钟）
function start()
{
 var today=new Date();
 var year=today.getFullYear();
 var month=today.getMonth()+1;
 var day=today.getDate();
 var hours=today.getHours();
 var minutes=today.getMinutes();
 var seconds=today.getSeconds();
 //如果是单位数字，前面补0
 month=month<10? "0"+month :month;
 day=day<10? "0"+day :day;
 hours=hours<10? "0"+hours :hours;
 minutes=minutes<10? "0"+minutes :minutes;
 seconds=seconds<10? "0"+seconds :seconds;
 //时间信息连成字符串
 var str="今天是"+year+"年"+month+"月"+day+"日 "+hours+":"+minutes+":"+seconds;
 //获取id=result的内容
 var obj=document.getElementById("result");
 obj.innerHTML=str;
 //延时器
 window.setTimeout("start()",1000);
}
</script>
</head>
 
<body onload="start()">
<div id="result"></div>
</body>
</html>