Wolfgang Bangert 

Folgenden Code habe ich online gefunden und geringfügig angepasst. Wenn man ihn in ein Formelfeld einfügt, läuft ein Countdown (im Browser). Ich habe es allerdings nicht geschafft, die Anfangszeit in einer Variable an das Skript zu übergeben (siehe rote Markierung). Vielleicht kennt sich hier jemand mit JS aus und hat eine Idee?
 

html("

<p id='demo'></p>

<script>
// Set the date we're counting down to
var countDownDate = new Date('July 5, 2022 17:00:00').getTime();

// Update the count down every 1 second
var x = setInterval(function() {

  // Get today's date and time
  var now = new Date().getTime();

// Find the distance between now and the count down date
  var distance = now - countDownDate;

// Time calculations for days, hours, minutes and seconds
  var days = Math.floor(distance / (1000 * 60 * 60 * 24));
  var hours = Math.floor((distance % (1000 * 60 * 60 * 24)) / (1000 * 60 * 60));
  var minutes = Math.floor((distance % (1000 * 60 * 60)) / (1000 * 60));
  var seconds = Math.floor((distance % (1000 * 60)) / 1000);

// Output the result in an element with id='demo'
  document.getElementById('demo').innerHTML = days + ' Tage ' + hours + ' Stunden ' + minutes + ' Minuten ' + seconds + ' Sekunden';

// If the count down is over, write some text 
  if (distance < 0) {
    clearInterval(x);
    document.getElementById('demo').innerHTML = 'EXPIRED';
  }
}, 1000);
</script>

")

Quelle:  https://www.w3schools.com/howto/howto_js_countdown.asp

Stefanie Kennes 

let startTime := number(datetime(2022, 7, 5, 17, 0, 0));
html("
<p id='demo'></p>
<script>
// Set the date we're counting down to
var countDownDate = " + startTime + ";
// Update the count down every 1 second
var x = setInterval(function() {
  // Get today's date and time
  var now = new Date().getTime();
// Find the distance between now and the count down date
  var distance = now - countDownDate;
// Time calculations for days, hours, minutes and seconds
  var days = Math.floor(distance / (1000 * 60 * 60 * 24));
  var hours = Math.floor((distance % (1000 * 60 * 60 * 24)) / (1000 * 60 * 60));
  var minutes = Math.floor((distance % (1000 * 60 * 60)) / (1000 * 60));
  var seconds = Math.floor((distance % (1000 * 60)) / 1000);
// Output the result in an element with id='demo'
  document.getElementById('demo').innerHTML = days + ' Tage ' + hours + ' Stunden ' + minutes + ' Minuten ' + seconds + ' Sekunden';
// If the count down is over, write some text 
  if (distance < 0) {
    clearInterval(x);
    document.getElementById('demo').innerHTML = 'EXPIRED';
  }
}, 1000);
</script>
")

Etienne Scherrer super, danke! Dann kann Wolfgang Bangert es ja so einbauen.

Etienne Scherrer super sache und wenn man das (now - countDownDate) rum dreht wirds nen countdown als kleine spielerei wenn feierabend ist