Convert seconds to HH-MM-SS with JavaScript?

Question

How can I convert seconds to an HH-MM-SS string using JavaScript?

Answer 1

Here is an extension to Number class. toHHMMSS() converts seconds to an hh:mm:ss string.

Number.prototype.toHHMMSS = function() {
  var hours = Math.floor(this / 3600) < 10 ? ("00" + Math.floor(this / 3600)).slice(-2) : Math.floor(this / 3600);
  var minutes = ("00" + Math.floor((this % 3600) / 60)).slice(-2);
  var seconds = ("00" + (this % 3600) % 60).slice(-2);
  return hours + ":" + minutes + ":" + seconds;
}

// Usage: [number variable].toHHMMSS();

// Here is a simple test
var totalseconds = 1234;
document.getElementById("timespan").innerHTML = totalseconds.toHHMMSS();

// HTML of the test