Incrementing a date in JavaScript

Question

I need to increment a date value by one day in JavaScript.

For example, I have a date value 2010-09-11 and I need to store the date of the next day in a JavaScript v

Answer 1

Timezone/daylight savings aware date increment for JavaScript dates:

function nextDay(date) {
    const sign = v => (v < 0 ? -1 : +1);
    const result = new Date(date.getTime());
    result.setDate(result.getDate() + 1);
    const offset = result.getTimezoneOffset();
    return new Date(result.getTime() + sign(offset) * offset * 60 * 1000);
}

Answer 2

 Date.prototype.AddDays = function (days) {
    days = parseInt(days, 10);
    return new Date(this.valueOf() + 1000 * 60 * 60 * 24 * days);
}

Example

var dt = new Date();
console.log(dt.AddDays(-30));
console.log(dt.AddDays(-10));
console.log(dt.AddDays(-1));
console.log(dt.AddDays(0));
console.log(dt.AddDays(1));
console.log(dt.AddDays(10));
console.log(dt.AddDays(30));

Result

2017-09-03T15:01:37.213Z
2017-09-23T15:01:37.213Z
2017-10-02T15:01:37.213Z
2017-10-03T15:01:37.213Z
2017-10-04T15:01:37.213Z
2017-10-13T15:01:37.213Z
2017-11-02T15:01:37.213Z

Answer 3

None of the examples in this answer seem to work with Daylight Saving Time adjustment days. On those days, the number of hours in a day are not 24 (they are 23 or 25, depending on if you are "springing forward" or "falling back".)

The below AddDays javascript function accounts for daylight saving time:

function addDays(date, amount) {
  var tzOff = date.getTimezoneOffset() * 60 * 1000,
      t = date.getTime(),
      d = new Date(),
      tzOff2;

  t += (1000 * 60 * 60 * 24) * amount;
  d.setTime(t);

  tzOff2 = d.getTimezoneOffset() * 60 * 1000;
  if (tzOff != tzOff2) {
    var diff = tzOff2 - tzOff;
    t += diff;
    d.setTime(t);
  }

  return d;
}

Here are the tests I used to test the function:

    var d = new Date(2010,10,7);
    var d2 = AddDays(d, 1);
    document.write(d.toString() + "<br />" + d2.toString());

    d = new Date(2010,10,8);
    d2 = AddDays(d, -1)
    document.write("<hr /><br />" +  d.toString() + "<br />" + d2.toString());

    d = new Date('Sun Mar 27 2011 01:59:00 GMT+0100 (CET)');
    d2 = AddDays(d, 1)
    document.write("<hr /><br />" +  d.toString() + "<br />" + d2.toString());

    d = new Date('Sun Mar 28 2011 01:59:00 GMT+0100 (CET)');
    d2 = AddDays(d, -1)
    document.write("<hr /><br />" +  d.toString() + "<br />" + d2.toString());

Answer 4

I feel that nothing is safer than .getTime() and .setTime(), so this should be the best, and performant as well.

const d = new Date()
console.log(d.setTime(d.getTime() + 1000 * 60 * 60 * 24)) // MILLISECONDS

.setDate() for invalid Date (like 31 + 1) is too dangerous, and it depends on the browser implementation.

Answer 5

Get the string value of the date using the dateObj.toJSON() method Ref: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/toJSON Slice the date from the returned value and then increment by the number of days you want.

var currentdate = new Date();
currentdate.setDate(currentdate.getDate() + 1);
var tomorrow = currentdate.toJSON().slice(0,10);

Answer 6

Via native JS, to add one day you may do following:

let date = new Date(); // today
date.setDate(date.getDate() + 1) // tomorrow

Another option is to use moment library:

const date = moment().add(14, "days").toDate()