15 分钟倒计时器

Question

I am running a 'just in time' webinar, where the webinar will be shown every '15, '30,' 45 and '60 past the hour.

I have a countdown timer configured to count down to the next quarter hour, but I also want the text to display something like:

'Next Webinar at 10:15AM'

At the moment, the text always displays the top of the hour time. Such as 10:00AM or 6:00PM, and doesn't show the 15, 30 or 45 intervals.

My question is: How do I configure the text to display the correct time for the next webinar and how do I configure the countdown to show the countdown until the next quarter hour?

Here is the code:

 <script> $(document).on("ready", function(){ // change to todays date: //$(".topHour_date").text( "(TODAY) " + moment().format('dddd MMMM Do') ); $(".topHour_date").text("NEXT CLASS TODAY "); // change next house $(".topHour_time").text( moment().add(0.1, 'hour').startOf('hour').format('h:mm A')); $time_now = moment().format("mm"); $time_now_difference = 15 - $time_now; $time_now_diff_seconds = $time_now_difference * 60; $.countdown.setDefaults($.countdown.regionalOptions["eng"]); $(".elCountdownEvergreen").countdown({ until: $time_now_diff_seconds, padZeroes: true }); }); </script>

Answer 1

Just copy and past the following code

<!-- Display the countdown timer in an element -->
<p id="demo"></p>

<script>
// Set the date we're counting down to
var countDownDate = new Date().getTime() + 15 * 60 * 1000;

// 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 = countDownDate - now;

  // Time calculations for hours, minutes and seconds
  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);

  // Display the result in the element with id="demo"
  document.getElementById("demo").innerHTML =  hours + ":"
  + minutes + ":" + seconds;

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

Answer 2

The question is lack of some important details about external scripts you require. I guess you use "moment.js" but can't identify the script you use to display the countdown.

In any case, the code you looking for (to calculate the next start period) is following:

var next = new Date(); // now
next.setTime(next.getTime() + 15 * 60 * 1000) // add 15 minutes
next.setMinutes(15 * Math.floor(next.getMinutes() / 15)) // rounding to the start of quarter or hour
next.setSeconds(0) // the period starts in 00 seconds of minute.

// format the output
next = moment(next).format('h:mm A')

// ... and display the next quarter of hour with
$('#some_output_div').text(next)