Java时间选择器实时插入

Question

在我有时钟的行中，它显示我登录时的时间，如何使其成为现实，所以它一直在滴答并显示实时。请查看图片（带有20.03.21 22:25的行）

带时间的厘米

<input type="text" class="light1" name="Date" value="[[:Date:]]" /><br/>
<input type="text" class="light1" id="txt" name="Now" readonly="readonly" value="[:NOW:]" />
<span style="position:relative; top:0px; left:0px;"><a href="javascript:;" onclick="$('#AddDataForm input[name=Date]').val($('#AddDataForm input[name=Now]').val());" style="text-decoration:none; position:absolute; right:3px; top:-2px;">&uarr;</a></span>

Answer 1

取自Clock and date javascript的代码

const pad = num => ("0" + num).slice(-2);
const timedate = () => {
  const currentTime = new Date(new Date().getTime() + diff);
  let hours = currentTime.getHours();
  const minutes = pad(currentTime.getMinutes());
  const seconds = pad(currentTime.getSeconds());

  const d = currentTime.getDate();
  const day = pad(d);
  const month = pad(currentTime.getMonth() + 1);
  const yyyy = currentTime.getFullYear();

/*  let dn = "PM"
  if (hours <= 12) dn = "AM";
  if (hours >= 12) hours -= 12;
  if (hours == 0) hours = 12; */
  hours = pad(hours);
  timeOutput.value = "" +
    yyyy + "/" + month + "/" + day +
    " " +
    hours + ":" +
    minutes + ":" +
    seconds// + dn;
}
let timeOutput;
let serverTime;
let diff;
window.addEventListener("load", function() {
  timeOutput = document.getElementById("timedate");
  serverTime = new Date("2020/03/21 22:23:24");// change to new Date("[[:Date:]]"); for example
  diff = new Date().getTime() - serverTime.getTime();
  setInterval(timedate, 1000);
});

<input type="text" id="timedate" class="light1" name="Date" value="" /><br/>