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Formatting JavaScript date

I have a string representing a date in the following format :
Jun 29, 2019 12:00:00 AM
I would like to format this date such as follows:
2019-06-29
Is there any way of doing this without using any external libraries?
I tried the following and it works fine in Chrome but not in Edge:
var stringDate = 'Jun 29, 2019 12:00:00 AM';
var date = new Date(stringDate).toISOString().slice(0,10);

Using an external lib like https://momentjs.com/ is of course the easiest option.
But if the dates are always in the format you say, maybe a little bit of regex and javascript might be all you need.
eg.
var resplitdate = /^(\w{3}) (\w{1,2}), (\w{4})/;
var months = 'Jan,Feb,Mar,Apr,May,Jun,Jul,Aug,Sep,Oct,Nov,Dec'.split(",");
function pz(s, size) {
var r = s.toString();
while (r.length < size) r = '0' + r;
return r;
}
function convertDate(d) {
var splits = resplitdate.exec(d);
return splits[3] + '-' +
pz(months.indexOf(splits[1]) + 1, 2) + "-" +
pz(splits[2], 2);
}
var stringDate = 'Jun 29, 2019 12:00:00 AM';
console.log(stringDate, " = ", convertDate(stringDate));

You can use getFullYear(), getDay() and getDate() to get the values. You can then use padStart() to pad the beginning of each item with zeros.
var date = new Date('Jun 29, 2019 12:00:00 AM');
console.log(`${date.getFullYear()}-${String(date.getDay()).padStart(2, '0')}-${String(date.getDate()).padStart(2, '0')}`)

A simple way to format the date using javascript(only) could be as follows -
var stringDate = 'Jun 29, 2019 12:00:00 AM';
function appendLeadingZeroes(n){
if(n <= 9){
return "0" + n;
}
return n
}
let current_datetime = new Date(stringDate);
let formatted_date = current_datetime.getFullYear() + "-" + appendLeadingZeroes(current_datetime.getMonth() + 1) + "-" + appendLeadingZeroes(current_datetime.getDate())
console.log(formatted_date)

How to convert date format into different formate

Hello I want to convert
March 2018 to 032018
in jQuery.I used
var d = new Date($('.selected_month').find("td:first").text());
But it is giving result is:
Thu Mar 01 2018 00:00:00 GMT+0530 (IST)

You need to use getMonth() and getFullYear() on returned date object to format date as per requirement. Also, you need to add 1 to returned month as getMonth method is 0 index based:
(d.getMonth()+1).toString() + d.getFullYear().toString()

Try this
function formatDate(date) {
var d = new Date(date),
month = '' + (d.getMonth() + 1),
year = d.getFullYear();
if (month.length < 2) month = '0' + month;
return [month,year].join('');
}
Call this function : formatDate('March 2018') // output : 032018

Try converting the date object you end up with to a string:
Try the following snippet, just change var d = new Date() to var d = new Date($('.selected_month').find("td:first").text()).
var d = new Date();
var twoDigitMonth = (d.getUTCMonth() + 1).toString().padStart(2, "0");
var year = d.getUTCFullYear();
var result = twoDigitMonth + year;
console.log(result);
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>

...or try this...
console.log(
new Date("March 2018")
.toLocaleDateString('en-EN', {month: '2-digit',year: 'numeric'})
.replace('/','')
)

Get date in Italian Format as "Lunedì GG/MM" how to?

i've tried to do this :
var curr = new Date;
var first = curr.getDate() - curr.getDay();
var last = first + 7;
var firstday = new Date(curr.setDate(first + 1)).toUTCString();
var lastday = new Date(curr.setDate(last)).toUTCString();
But i get firstday = "Mon, 18 Jan 2016 09:14:44 GMT" and
lastday = "Sun, 24 Jan 2016 09:14:44 GMT". How can i use italian name of the day and format DD/MM as "Lunedì 10/01" (Monday 10 of January in english).
Thanks
Cris

Without having to use external libraries, you want to use the toLocaleString() function.
var options = {'weekday': 'long', 'month': '2-digit', 'day': '2-digit'};
var date = new Date().toLocaleString('it-IT', options);
document.write(date)
Reference with all the possible options

Use moment.js for that
moment.locale('it');
document.write(moment().format('dddd DD/MM'));
<script src="https://cdnjs.cloudflare.com/ajax/libs/moment.js/2.11.1/moment.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/moment.js/2.11.1/locale/it.js"></script>

hi you can do it by using moment.js ,By default, Moment.js comes with English locale strings. If you need other locales, you can load them into Moment.js like this:
moment.locale('it');
var currentDate = moment();
//fist
alert(moment().format('dddd, MMMM Do YYYY, h:mm:ss'));
//last
alert(currentDate.add(7, 'days').format('dddd, MMMM Do YYYY, h:mm:ss'));
this a working demo

with this approach you can craft every custom format:
function italianTimeFormat (dateUTC) {
if (dateUTC) {
let jsDateFormat = new Date(dateUTC)
let fullStringTime = {
day: Number(jsDateFormat.getDate() < 10) ? '0' + jsDateFormat.getDate() : jsDateFormat.getDate(),
month: Number((jsDateFormat.getMonth() + 1)) < 10 ? '0' + (jsDateFormat.getMonth() + 1) : (jsDateFormat.getMonth() + 1),
year: jsDateFormat.getFullYear(),
hours: Number(jsDateFormat.getHours()) < 10 ? '0' + jsDateFormat.getHours() : jsDateFormat.getHours(),
minutes: Number(jsDateFormat.getMinutes()) < 10 ? '0' + jsDateFormat.getMinutes() : jsDateFormat.getMinutes()
}
return fullStringTime.day + '/' + fullStringTime.month + '/' + fullStringTime.year + ' ' +
fullStringTime.hours + ':' + fullStringTime.minutes
}
return null
}
let today = Date.now();
document.write(italianTimeFormat(today))
I hope i've been helpful for someone

How do I get a date in YYYY-MM-DD format?

Normally if I wanted to get the date I could just do something like
var d = new Date();
console.log(d);
The problem with doing that, is when I run that code, it returns:
Mon Aug 24 2015 4:20:00 GMT-0800 (Pacific Standard Time)
How could I get the Date() method to return a value in a "MM-DD-YYYY" format so it would return something like:
8/24/2015
Or, maybe MM-DD-YYYY H:M
8/24/2016 4:20

Just use the built-in .toISOString() method like so: toISOString().split('T')[0]. Simple, clean and all in a single line.
var date = (new Date()).toISOString().split('T')[0];
document.getElementById('date').innerHTML = date;
<div id="date"></div>
Please note that the timezone of the formatted string is UTC rather than local time.

The below code is a way of doing it. If you have a date, pass it to the convertDate() function and it will return a string in the YYYY-MM-DD format:
var todaysDate = new Date();
function convertDate(date) {
var yyyy = date.getFullYear().toString();
var mm = (date.getMonth()+1).toString();
var dd = date.getDate().toString();
var mmChars = mm.split('');
var ddChars = dd.split('');
return yyyy + '-' + (mmChars[1]?mm:"0"+mmChars[0]) + '-' + (ddChars[1]?dd:"0"+ddChars[0]);
}
console.log(convertDate(todaysDate)); // Returns: 2015-08-25

Yet another way:
var today = new Date().getFullYear()+'-'+("0"+(new Date().getMonth()+1)).slice(-2)+'-'+("0"+new Date().getDate()).slice(-2)
document.getElementById("today").innerHTML = today
<div id="today">

By using Moment.js library, you can do:
var datetime = new Date("2015-09-17 15:00:00");
datetime = moment(datetime).format("YYYY-MM-DD");

var today = new Date();
function formatDate(date) {
var dd = date.getDate();
var mm = date.getMonth() + 1; //January is 0!
var yyyy = date.getFullYear();
if (dd < 10) {
dd = '0' + dd;
}
if (mm < 10) {
mm = '0' + mm;
}
//return dd + '/' + mm + '/' + yyyy;
return yyyy + '/' + mm + '/' +dd ;
}
console.log(formatDate(today));

function formatdate(userDate){
var omar= new Date(userDate);
y = omar.getFullYear().toString();
m = omar.getMonth().toString();
d = omar.getDate().toString();
omar=y+m+d;
return omar;
}
console.log(formatDate("12/31/2014"));

What you want to achieve can be accomplished with native JavaScript. The object Date has methods that generate exactly the output you wish.
Here are code examples:
var d = new Date();
console.log(d);
>>> Sun Jan 28 2018 08:28:04 GMT+0000 (GMT)
console.log(d.toLocaleDateString());
>>> 1/28/2018
console.log(d.toLocaleString());
>>> 1/28/2018, 8:28:04 AM
There is really no need to reinvent the wheel.

If you are trying to get the 'local-ISO' date string. Try the code below.
function (date) {
return new Date(+date - date.getTimezoneOffset() * 60 * 1000).toISOString().split(/[TZ]/).slice(0, 2).join(' ');
}
+date Get milliseconds from a date.
Ref: Date.prototype.getTimezoneOffset
Have fun with it :)

Here is a simple function I created when once I kept working on a project where I constantly needed to get today, yesterday, and tomorrow's date in this format.
function returnYYYYMMDD(numFromToday = 0){
let d = new Date();
d.setDate(d.getDate() + numFromToday);
const month = d.getMonth() < 9 ? '0' + (d.getMonth() + 1) : d.getMonth() + 1;
const day = d.getDate() < 10 ? '0' + d.getDate() : d.getDate();
return `${d.getFullYear()}-${month}-${day}`;
}
console.log(returnYYYYMMDD(-1)); // returns yesterday
console.log(returnYYYYMMDD()); // returns today
console.log(returnYYYYMMDD(1)); // returns tomorrow
Can easily be modified to pass it a date instead, but here you pass a number and it will return that many days from today.

If you're not opposed to adding a small library, Date-Mirror (NPM or unpkg) allows you to format an existing date in YYYY-MM-DD into whatever date string format you'd like.
date('n/j/Y', '2020-02-07') // 2/7/2020
date('n/j/Y g:iA', '2020-02-07 4:45PM') // 2/7/2020 4:45PM
date('n/j [until] n/j', '2020-02-07', '2020-02-08') // 2/7 until 2/8
Disclaimer: I developed Date-Mirror.

This will convert a unix timestamp to local date (+ time)
function UnixTimeToLocalDate = function( unix_epoch_time )
{
var date,
str;
date = new Date( unix_epoch_time * 1000 );
str = date.getFullYear() + '-' +
(date.getMonth() + 1 + '').padStart( 2, '0' ) + '-' +
(date.getDate() + '').padStart( 2, '0' );
// If you need hh:mm:ss too then
str += ' ' +
(date.getHours() + '').padStart( 2, '0' ) + ':' +
(date.getMinutes() + '').padStart( 2, '0' ) + ':' +
(date.getSeconds() + '').padStart( 2, '0' );
return str;
}

If you want a text format that's good for sorting use:
function formatDateYYYYMMDDHHMMSS(date){
// YYYY-MM-DD HH:MM:SS
const datePart = date.toISOString().split("T")[0]
const timePart = date.toLocaleString('en-US', {hour12: false}).split(",")[1]
return datePart + timePart
}
As prototype:
Date.prototype.toSortString = function(){
const date = new Date(this.valueOf());
return date.toISOString().split("T")[0] +
date.toLocaleString('en-US', {hour12: false}).split(",")[1]
}

Simple one line elegant solution for fullYear-fullMonth-FullDay as '2000-01-01'
new Date().toLocaleDateString("fr-CA",
{year:"numeric", month: "2-digit", day:"2-digit"}
)

const padTo2Digits = num => {
return num.toString().padStart(2, '0')
}
const formatDate = date => {
return [
date.getFullYear(),
padTo2Digits(date.getMonth() + 1),
padTo2Digits(date.getDate())
].join('-')
}
let value = formatDate(new Date())
document.getElementById('dayFormatUS').innerHTML = value
const transformDate = date => {
const convert = date.split('-').reverse()
return convert.join('/')
}
document.getElementById('dayFormatBR').innerHTML = transformDate(value)
<div>
Format US -
<span id='dayFormatUS'></span>
</div>
<div>
Format BR -
<span id='dayFormatBR'></span>
</div>

Incrementing a date in JavaScript

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 variable.
How can I increment a date by a day?

Three options for you:
1. Using just JavaScript's Date object (no libraries):
My previous answer for #1 was wrong (it added 24 hours, failing to account for transitions to and from daylight saving time; Clever Human pointed out that it would fail with November 7, 2010 in the Eastern timezone). Instead, Jigar's answer is the correct way to do this without a library:
// To do it in local time
var tomorrow = new Date();
tomorrow.setDate(tomorrow.getDate() + 1);
// To do it in UTC
var tomorrow = new Date();
tomorrow.setUTCDate(tomorrow.getUTCDate() + 1);
This works even for the last day of a month (or year), because the JavaScript date object is smart about rollover:
// (local time)
var lastDayOf2015 = new Date(2015, 11, 31);
console.log("Last day of 2015: " + lastDayOf2015.toISOString());
var nextDay = new Date(+lastDayOf2015);
var dateValue = nextDay.getDate() + 1;
console.log("Setting the 'date' part to " + dateValue);
nextDay.setDate(dateValue);
console.log("Resulting date: " + nextDay.toISOString());
2. Using MomentJS:
var today = moment();
var tomorrow = moment(today).add(1, 'days');
(Beware that add modifies the instance you call it on, rather than returning a new instance, so today.add(1, 'days') would modify today. That's why we start with a cloning op on var tomorrow = ....)
3. Using DateJS, but it hasn't been updated in a long time:
var today = new Date(); // Or Date.today()
var tomorrow = today.add(1).day();

var myDate = new Date();
//add a day to the date
myDate.setDate(myDate.getDate() + 1);

The easiest way is to convert to milliseconds and add 1000*60*60*24 milliseconds e.g.:
var tomorrow = new Date(today.getTime()+1000*60*60*24);

Tomorrow in one line in pure JS but it's ugly !
new Date(new Date().setDate(new Date().getDate() + 1))
Here is the result :
Thu Oct 12 2017 08:53:30 GMT+0200 (Romance Summer Time)

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());

You first need to parse your string before following the other people's suggestion:
var dateString = "2010-09-11";
var myDate = new Date(dateString);
//add a day to the date
myDate.setDate(myDate.getDate() + 1);
If you want it back in the same format again you will have to do that "manually":
var y = myDate.getFullYear(),
m = myDate.getMonth() + 1, // january is month 0 in javascript
d = myDate.getDate();
var pad = function(val) { var str = val.toString(); return (str.length < 2) ? "0" + str : str};
dateString = [y, pad(m), pad(d)].join("-");
But I suggest getting Date.js as mentioned in other replies, that will help you alot.

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.

Getting the next 5 days:
var date = new Date(),
d = date.getDate(),
m = date.getMonth(),
y = date.getFullYear();
for(i=0; i < 5; i++){
var curdate = new Date(y, m, d+i)
console.log(curdate)
}

Two methods:
1:
var a = new Date()
// no_of_days is an integer value
var b = new Date(a.setTime(a.getTime() + no_of_days * 86400000)
2: Similar to the previous method
var a = new Date()
// no_of_days is an integer value
var b = new Date(a.setDate(a.getDate() + no_of_days)

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()

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);

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

Not entirelly sure if it is a BUG(Tested Firefox 32.0.3 and Chrome 38.0.2125.101), but the following code will fail on Brazil (-3 GMT):
Date.prototype.shiftDays = function(days){
days = parseInt(days, 10);
this.setDate(this.getDate() + days);
return this;
}
$date = new Date(2014, 9, 16,0,1,1);
$date.shiftDays(1);
console.log($date+"");
$date.shiftDays(1);
console.log($date+"");
$date.shiftDays(1);
console.log($date+"");
$date.shiftDays(1);
console.log($date+"");
Result:
Fri Oct 17 2014 00:01:01 GMT-0300
Sat Oct 18 2014 00:01:01 GMT-0300
Sat Oct 18 2014 23:01:01 GMT-0300
Sun Oct 19 2014 23:01:01 GMT-0200
Adding one Hour to the date, will make it work perfectly (but does not solve the problem).
$date = new Date(2014, 9, 16,0,1,1);
Result:
Fri Oct 17 2014 01:01:01 GMT-0300
Sat Oct 18 2014 01:01:01 GMT-0300
Sun Oct 19 2014 01:01:01 GMT-0200
Mon Oct 20 2014 01:01:01 GMT-0200

Results in a string representation of tomorrow's date. Use new Date() to get today's date, adding one day using Date.getDate() and Date.setDate(), and converting the Date object to a string.
const tomorrow = () => {
let t = new Date();
t.setDate(t.getDate() + 1);
return `${t.getFullYear()}-${String(t.getMonth() + 1).padStart(2, '0')}-${String(
t.getDate()
).padStart(2, '0')}`;
};
tomorrow();

Incrementing date's year with vanilla js:
start_date_value = "01/01/2019"
var next_year = new Date(start_date_value);
next_year.setYear(next_year.getYear() + 1);
console.log(next_year.getYear()); //=> 2020
Just in case someone wants to increment other value than the date (day)

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);
}

This a simpler method ,
and it will return the date in simple yyyy-mm-dd format , Here it is
function incDay(date, n) {
var fudate = new Date(new Date(date).setDate(new Date(date).getDate() + n));
fudate = fudate.getFullYear() + '-' + (fudate.getMonth() + 1) + '-' + fudate.toDateString().substring(8, 10);
return fudate;
}
example :
var tomorrow = incDay(new Date(), 1); // the next day of today , aka tomorrow :) .
var spicaldate = incDay("2020-11-12", 1); // return "2020-11-13" .
var somedate = incDay("2020-10-28", 5); // return "2020-11-02" .
Note
incDay(new Date("2020-11-12"), 1);
incDay("2020-11-12", 1);
will return the same result .

Use this function, it´s solved my problem:
let nextDate = (daysAhead:number) => {
const today = new Date().toLocaleDateString().split('/')
const invalidDate = new Date(`${today[2]}/${today[1]}/${Number(today[0])+daysAhead}`)
if(Number(today[1]) === Number(12)){
return new Date(`${Number(today[2])+1}/${1}/${1}`)
}
if(String(invalidDate) === 'Invalid Date'){
return new Date(`${today[2]}/${Number(today[1])+1}/${1}`)
}
return new Date(`${today[2]}/${Number(today[1])}/${Number(today[0])+daysAhead}`)
}

Assigning the Increment of current date to other Variable
let startDate=new Date();
let endDate=new Date();
endDate.setDate(startDate.getDate() + 1)
console.log(startDate,endDate)