javascript简易动态时间代码

javascript简易动态时间效果如下：

 

<div align="center" id="showtime"> </div>
<script type="text/javascript">
window.onload = function() {
var showtime = document.getElementById("showtime");
setInterval(function() {
var time = new Date();
var m = time.getMonth() + 1;
var t = time.getFullYear() + "-" + m + "-" + time.getDate() + " " + time.getHours() + ":" + time.getMinutes() + ":" + time.getSeconds();
showtime.innerHTML = t;
}, 1000);
};
</script>