Differenza date in JavaScript

Questa funzione permette di eseguire una differenza tra due date JavaScript e ritornare un oggetto con la differenza espressa in: giorni, ore, minuti e secondi:

JavaScriptCopia

var sgart = sgart || {};
sgart.date = sgart.date || {};

sgart.date.diff =  function (dt1, dt2) {
  const cSeconds = 1000, cMinutes = cSeconds * 60, cHours = cMinutes * 60, cDays = cHours * 24;
  const diff = dt1 -dt2;
  const df = diff / cDays, d = parseInt(df), dDiff = parseInt((df - d) * cDays);
  const hf = dDiff / cHours, h = parseInt(hf), hDiff = parseInt((hf - h) * cHours);
  const mf = hDiff / cMinutes, m = parseInt(mf), mDiff = parseInt((mf - m) * cMinutes);
  const sf = mDiff / cSeconds, s = parseInt(sf), sDiff = parseInt((sf - s) * cSeconds);

  return { d: d, h: h, m: m, s: s };
};

sgart.date.diff(new Date(), new Date(2017, 07, 5, 8, 24, 10));

ritorna un oggetto tipo:

JavaScriptCopia

{"d":32,"h":3,"m":45,"s":30}

che posso formattare con:

JavaScriptCopia

sgart.date.diffString =  function (dt1, dt2) {
  const r= sgart.date.diff(dt1, dt2);
  return  r.d + 'd ' + r.h + 'h ' + r.m + 'm ' + r.s + 's';
};

sgart.date.diffString(new Date(), new Date(2017, 07, 5, 8, 24, 10));

che ritorna:

JavaScriptCopia

32d 3h 45m 30s

Esempio: