<!DOCTYPE HTML>
<html>
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>显示当前时间</title>
</head>
<body>
<input type="text" size="10" style="background-color: lightyellow; border-width: 3;" id='input_id' value=''/>
</body>
<script type="text/javascript">
var inputid = document.getElementById("input_id");
function showtime(){
var now_time = new Date();//创建时间对象的实例
var hours = now_time.getHours();//获得当前小时数
var minutes = now_time.getMinutes();//获得当前分钟数
var seconds = now_time.getSeconds();//获得当前秒数
var timer = ""+((hours>12)?hours-12:hours);//将小时数值赋予变量timer
timer += ((minutes<10)?":0":":") + minutes;//将分钟数值赋予变量timer
timer += ((seconds<10)?":0":":") + seconds;//将秒数值赋予变量timer
timer +=" " + ((hours>12)?"pm":"am");//将数字am或者pm赋予变量timer
inputid.value = timer
setTimeout("showtime()",1000);//设置每隔一秒钟自动调用一次showtime()函数
}
window.onload=showtime()
</script>
</html>
结果如图: