<p id="currentTime">
</p>
<script>
document.getElementById("currentTime").innerHTML = new Date();//初始化時間
var timing = setInterval(function(){changeTime()},1000);//設置定時執行方法和執行頻率
function changeTime(){
document.getElementById("currentTime").innerHTML = new Date();//改變內容
console.log(new Date());//像控制臺打印內容
}
</script>