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Add trailing zero in time format in jquery [duplicate]

I've created this script to calculate the date for 10 days in advance in the format of dd/mm/yyyy:
var MyDate = new Date();
var MyDateString = new Date();
MyDate.setDate(MyDate.getDate()+10);
MyDateString = MyDate.getDate() + '/' + (MyDate.getMonth()+1) + '/' + MyDate.getFullYear();
I need to have the date appear with leading zeroes on the day and month component by way of adding these rules to the script. I can't seem to get it to work.
if (MyDate.getMonth < 10)getMonth = '0' + getMonth;
and
if (MyDate.getDate <10)get.Date = '0' + getDate;
If someone could show me where to insert these into the script I would be really appreciative.

Try this: http://jsfiddle.net/xA5B7/
var MyDate = new Date();
var MyDateString;
MyDate.setDate(MyDate.getDate() + 20);
MyDateString = ('0' + MyDate.getDate()).slice(-2) + '/'
+ ('0' + (MyDate.getMonth()+1)).slice(-2) + '/'
+ MyDate.getFullYear();
EDIT:
To explain, .slice(-2) gives us the last two characters of the string.
So no matter what, we can add "0" to the day or month, and just ask for the last two since those are always the two we want.
So if the MyDate.getMonth() returns 9, it will be:
("0" + "9") // Giving us "09"
so adding .slice(-2) on that gives us the last two characters which is:
("0" + "9").slice(-2)
"09"
But if MyDate.getMonth() returns 10, it will be:
("0" + "10") // Giving us "010"
so adding .slice(-2) gives us the last two characters, or:
("0" + "10").slice(-2)
"10"

The modern way
The new modern way to do this is to use toLocaleDateString, because it allows you not only to format a date with proper localization, but even to pass format options to achieve the desired result:
const date = new Date(2018, 2, 1)
const result = date.toLocaleDateString("en-GB", { // you can use undefined as first argument
year: "numeric",
month: "2-digit",
day: "2-digit",
})
console.log(result) // outputs “01/03/2018”
Or using a Temporal object (still in proposal, caniuse):
const date = new Temporal.PlainDate(2018, 3, 1) // also works with zoned date
const result = date.toLocaleString("en-GB", { // you can use undefined as first argument
year: "numeric",
month: "2-digit",
day: "2-digit",
})
console.log(result) // outputs “01/03/2018”
When you use undefined as the first argument it will detect the browser language, instead. Alternatively, you can use 2-digit on the year option, too.
Performance
If you plan to format a lot of dates, you should consider using Intl.DateTimeFormat instead:
const formatter = new Intl.DateTimeFormat("en-GB", { // <- re-use me
year: "numeric",
month: "2-digit",
day: "2-digit",
})
const date = new Date(2018, 2, 1) // can also be a Temporal object
const result = formatter.format(date)
console.log(result) // outputs “01/03/2018”
The formatter is compatible with Date and Temporal objects.
Historical dates
Unlike in the Temporal constructor years between 0 and 99 will be interpreted as 20th century years on the Date constructor. To prevent this, initialize the date like so:
const date = new Date()
date.setFullYear(18, 2, 1) // the year is A.D. 18
This is not required for Temporal objects, but years below 1000 will not contain leading zeros in all cases, because the formatter (that is shared for the Date and Temporal API) does not support 4-digit formatting at all. In this case you have to do manual formatting (see below).
For the ISO 8601 format
If you want to get your date in the YYYY-MM-DD format (ISO 8601), the solution looks different:
const date = new Date(Date.UTC(2018, 2, 1))
const result = date.toISOString().split('T')[0]
console.log(result) // outputs “2018-03-01”
Your input date should be in the UTC format or toISOString() will fix that for you. This is done by using Date.UTC as shown above.
Historical dates for the ISO 8601 format
Unlike in the Temporal constructor years between 0 and 99 will be interpreted as 20th century years on the Date constructor. To prevent this, initialize the date like so to be used for the ISO 8601 format:
const date = new Date()
date.setUTCFullYear(18, 2, 1) // the year is A.D. 18
Note that the ISO format for Temporal objects with dates before the year 1000 or after the year 9999 will have a different formatting compared to the legacy Date API. It is recommend to fallback to custom formatting to enforce 4 digit years in all circumstances.
Custom 4-digit formatting on the year
Sadly, the formatter doesn't support leading zeros on the year. There is no 4-digit option. This will remain for Temporal objects as well, because they do share the same formatter.
Fortunately, the ISO format of the Date API will always display at least 4 digits on the year, although Temporal objects do not. So at least for the Date API you can format historical dates before the year 1000 with leading zeros by falling back to a manual formatting approach using part of the ISO 8601 format method:
const date = new Date()
date.setUTCFullYear(18, 2, 1)
const ymd = date.toISOString().split('T')[0].split('-')
const result = `${ymd[2]}/${ymd[1]}/${ymd[0]}`
console.log(result) // outputs “01/03/0018”
For a Temporal object a different route is necessary, since the ISOYearString will be formatted differently for dates before the year 1000 and after the year 9999 as mentioned before:
const date = new Temporal.PlainDate(2018, 3, 1) // also works with zoned date
const zeroPad = (n, digits) => n.toString().padStart(digits, '0');
const result = `${zeroPad(date.day, 2)}/${zeroPad(date.month, 2)}/${zeroPad(date.year, 4)}`;
console.log(result) // outputs “01/03/0018”
Miscellaneous
For the Date and Temporal API there is also toLocaleTimeString, that allows you to localize and format the time of a date.

Here is an example from the Date object docs on the Mozilla Developer Network using a custom "pad" function, without having to extend Javascript's Number prototype. The handy function they give as an example is
function pad(n){return n<10 ? '0'+n : n}
And below is it being used in context.
/* use a function for the exact format desired... */
function ISODateString(d){
function pad(n){return n<10 ? '0'+n : n}
return d.getUTCFullYear()+'-'
+ pad(d.getUTCMonth()+1)+'-'
+ pad(d.getUTCDate())+'T'
+ pad(d.getUTCHours())+':'
+ pad(d.getUTCMinutes())+':'
+ pad(d.getUTCSeconds())+'Z'
}
var d = new Date();
console.log(ISODateString(d)); // prints something like 2009-09-28T19:03:12Z

For you people from the future (ECMAScript 2017 and beyond)
Solution
"use strict"
const today = new Date()
const year = today.getFullYear()
const month = `${today.getMonth() + 1}`.padStart(2, "0")
const day = `${today.getDate()}`.padStart(2, "0")
const stringDate = [day, month, year].join("/") // 13/12/2017
Explaination
the String.prototype.padStart(targetLength[, padString]) adds as many as possible padString in the String.prototype target so that the new length of the target is targetLength.
Example
"use strict"
let month = "9"
month = month.padStart(2, "0") // "09"
let byte = "00000100"
byte = byte.padStart(8, "0") // "00000100"

You can define a "str_pad" function (as in php):
function str_pad(n) {
return String("00" + n).slice(-2);
}

I found the shorterst way to do this:
MyDateString.replace(/(^|\D)(\d)(?!\d)/g, '$10$2');
will add leading zeros to all lonely, single digits

Number.prototype.padZero= function(len){
var s= String(this), c= '0';
len= len || 2;
while(s.length < len) s= c + s;
return s;
}
//in use:
(function(){
var myDate= new Date(), myDateString;
myDate.setDate(myDate.getDate()+10);
myDateString= [myDate.getDate().padZero(),
(myDate.getMonth()+1).padZero(),
myDate.getFullYear()].join('/');
alert(myDateString);
})()
/* value: (String)
09/09/2010
*/

Nowadays you can also utilize String.prototype.padStart to reach the goal in quick and easy way
String(new Date().getMonth() + 1).padStart(2, '0')
The availability can be assessed at caniuse
var date = new Date()
var year = date.getFullYear()
var month = String(date.getMonth() + 1).padStart(2, '0')
var day = String(date.getDate()).padStart(2, '0')
console.log('%s/%s/%s', month, day, year)
Check
var date = new Date('7/4/2021')
var year = date.getFullYear()
var month = String(date.getMonth() + 1).padStart(2, '0')
var day = String(date.getDate()).padStart(2, '0')
/**
* Expected output: 07/04/2021
*/
console.log('%s/%s/%s', month, day, year)
Polyfill for old browsers
String.prototype.padStart || Object.defineProperty(String.prototype, 'padStart', {
configurable : true,
writable : true,
value : function (targetLength, padString) {
'use strict'
/**
* String.prototype.padStart polyfill
* https://stackoverflow.com/questions/3605214/javascript-add-leading-zeroes-to-date
*/
targetLength = targetLength | 0
padString = arguments.length > 1 ? String(padString) : ' '
if (this.length < targetLength && padString.length) {
targetLength = targetLength - this.length
while (padString.length < targetLength) {
padString += padString
}
return padString.slice(0, targetLength) + this
} else {
return this
}
}
})

var MyDate = new Date();
var MyDateString = '';
MyDate.setDate(MyDate.getDate());
var tempoMonth = (MyDate.getMonth()+1);
var tempoDate = (MyDate.getDate());
if (tempoMonth < 10) tempoMonth = '0' + tempoMonth;
if (tempoDate < 10) tempoDate = '0' + tempoDate;
MyDateString = tempoDate + '/' + tempoMonth + '/' + MyDate.getFullYear();

There is another approach to solve this problem, using slice in JavaScript.
var d = new Date();
var datestring = d.getFullYear() + "-" + ("0"+(d.getMonth()+1)).slice(-2) +"-"+("0" + d.getDate()).slice(-2);
the datestring return date with format as you expect: 2019-09-01
another approach is using dateformat library: https://github.com/felixge/node-dateformat

You could use ternary operator to format the date like an "if" statement.
For example:
var MyDate = new Date();
MyDate.setDate(MyDate.getDate()+10);
var MyDateString = (MyDate.getDate() < 10 ? '0' + MyDate.getDate() : MyDate.getDate()) + '/' + ((d.getMonth()+1) < 10 ? '0' + (d.getMonth()+1) : (d.getMonth()+1)) + '/' + MyDate.getFullYear();
So
(MyDate.getDate() < 10 ? '0' + MyDate.getDate() : MyDate.getDate())
would be similar to an if statement, where if the getDate() returns a value less than 10, then return a '0' + the Date, or else return the date if greater than 10 (since we do not need to add the leading 0). Same for the month.
Edit:
Forgot that getMonth starts with 0, so added the +1 to account for it. Of course you could also just say d.getMonth() < 9 :, but I figured using the +1 would help make it easier to understand.

function formatDate(jsDate){
// add leading zeroes to jsDate when days or months are < 10..
// i.e.
// formatDate(new Date("1/3/2013"));
// returns
// "01/03/2103"
////////////////////
return (jsDate.getDate()<10?("0"+jsDate.getDate()):jsDate.getDate()) + "/" +
((jsDate.getMonth()+1)<10?("0"+(jsDate.getMonth()+1)):(jsDate.getMonth()+1)) + "/" +
jsDate.getFullYear();
}

You can provide options as a parameter to format date. First parameter is for locale which you might not need and second is for options.
For more info visit
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/toLocaleDateString
var date = new Date(Date.UTC(2012, 1, 1, 3, 0, 0));
var options = { year: 'numeric', month: '2-digit', day: '2-digit' };
console.log(date.toLocaleDateString(undefined,options));

I wrapped the correct answer of this question in a function that can add multiple leading zero's but defaults to adding 1 zero.
function zeroFill(nr, depth){
depth = (depth === undefined)? 1 : depth;
var zero = "0";
for (var i = 0; i < depth; ++i) {
zero += "0";
}
return (zero + nr).slice(-(depth + 1));
}
for working with numbers only and not more than 2 digits, this is also an approach:
function zeroFill(i) {
return (i < 10 ? '0' : '') + i
}

Another option, using a built-in function to do the padding (but resulting in quite long code!):
myDateString = myDate.getDate().toLocaleString('en-US', {minimumIntegerDigits: 2})
+ '/' + (myDate.getMonth()+1).toLocaleString('en-US', {minimumIntegerDigits: 2})
+ '/' + myDate.getFullYear();
// '12/06/2017'
And another, manipulating strings with regular expressions:
var myDateString = myDate.toISOString().replace(/T.*/, '').replace(/-/g, '/');
// '2017/06/12'
But be aware that one will show the year at the start and the day at the end.

Adding on to #modiX answer, this is what works...DO NOT LEAVE THAT as empty
today.toLocaleDateString("default", {year: "numeric", month: "2-digit", day: "2-digit"})

Here is very simple example how you can handle this situation.
var mydate = new Date();
var month = (mydate.getMonth().toString().length < 2 ? "0"+mydate.getMonth().toString() :mydate.getMonth());
var date = (mydate.getDate().toString().length < 2 ? "0"+mydate.getDate().toString() :mydate.getDate());
var year = mydate.getFullYear();
console.log("Format Y-m-d : ",year+"-"+month+"-" + date);
console.log("Format Y/m/d : ",year+"/"+month+"/" + date);

I think this solution is easier and can be easily remembered:
var MyDate = new Date();
var day = MyDate.getDate() + 10; // 10 days in advance
var month = MyDate.getMonth() + 1; // since months start from 0 we should add 1 to it
var year = MyDate.getFullYear();
day = checkDate(day);
month = checkDate(month);
function checkDate(i){
if(i < 10){
i = '0' + i;
}
return i;
}
console.log(`${month}/${day}/${year}`);

What I would do, is create my own custom Date helper that looks like this :
var DateHelper = {
addDays : function(aDate, numberOfDays) {
aDate.setDate(aDate.getDate() + numberOfDays); // Add numberOfDays
return aDate; // Return the date
},
format : function format(date) {
return [
("0" + date.getDate()).slice(-2), // Get day and pad it with zeroes
("0" + (date.getMonth()+1)).slice(-2), // Get month and pad it with zeroes
date.getFullYear() // Get full year
].join('/'); // Glue the pieces together
}
}
// With this helper, you can now just use one line of readable code to :
// ---------------------------------------------------------------------
// 1. Get the current date
// 2. Add 20 days
// 3. Format it
// 4. Output it
// ---------------------------------------------------------------------
document.body.innerHTML = DateHelper.format(DateHelper.addDays(new Date(), 20));
(see also this Fiddle)

As #John Henckel suggests, starting using the toISOString() method makes things easier
const dateString = new Date().toISOString().split('-');
const year = dateString[0];
const month = dateString[1];
const day = dateString[2].split('T')[0];
console.log(`${year}-${month}-${day}`);

try this for a basic function, no libraries required
Date.prototype.CustomformatDate = function() {
var tmp = new Date(this.valueOf());
var mm = tmp.getMonth() + 1;
if (mm < 10) mm = "0" + mm;
var dd = tmp.getDate();
if (dd < 10) dd = "0" + dd;
return mm + "/" + dd + "/" + tmp.getFullYear();
};

You could simply use :
const d = new Date();
const day = `0${d.getDate()}`.slice(-2);
So a function could be created like :
AddZero(val){
// adding 0 if the value is a single digit
return `0${val}`.slice(-2);
}
Your new code :
var MyDate = new Date();
var MyDateString = new Date();
MyDate.setDate(MyDate.getDate()+10);
MyDateString = AddZero(MyDate.getDate()) + '/' + AddZero(MyDate.getMonth() + 1) + '/' + MyDate.getFullYear();

toISOString can get leading 0
const currentdate = new Date();
const date = new Date(Date.UTC(currentdate.getFullYear(), (currentdate.getMonth()),currentdate.getDate(), currentdate.getHours(), currentdate.getMinutes(), currentdate.getSeconds()));
//you can pass YY, MM, DD //op: 2018-03-01
//i have passed YY, MM, DD, HH, Min, Sec // op : 2021-06-09T12:14:27.000Z
console.log(date.toISOString());
output will be similar to this : 2021-06-09T12:14:27.000Z

const month = date.toLocaleDateString('en-US', { month: '2-digit' });
const day = date.toLocaleDateString('en-US', { day: '2-digit' });
const year = date.getFullYear();
const dateString = `${month}-${day}-${year}`;

The following aims to extract configuration, hook into Date.protoype and apply configuration.
I've used an Array to store time chunks and when I push() this as a Date object, it returns me the length to iterate. When I'm done, I can use join on the return value.
This seems to work pretty fast: 0.016ms
// Date protoype
Date.prototype.formatTime = function (options) {
var i = 0,
time = [],
len = time.push(this.getHours(), this.getMinutes(), this.getSeconds());
for (; i < len; i += 1) {
var tick = time[i];
time[i] = tick < 10 ? options.pad + tick : tick;
}
return time.join(options.separator);
};
// Setup output
var cfg = {
fieldClock: "#fieldClock",
options: {
pad: "0",
separator: ":",
tick: 1000
}
};
// Define functionality
function startTime() {
var clock = $(cfg.fieldClock),
now = new Date().formatTime(cfg.options);
clock.val(now);
setTimeout(startTime, cfg.options.tick);
}
// Run once
startTime();
demo: http://jsfiddle.net/tive/U4MZ3/

Add some padding to allow a leading zero - where needed - and concatenate using your delimiter of choice as string.
Number.prototype.padLeft = function(base,chr){
var len = (String(base || 10).length - String(this).length)+1;
return len > 0? new Array(len).join(chr || '0')+this : this;
}
var d = new Date(my_date);
var dformatted = [(d.getMonth()+1).padLeft(), d.getDate().padLeft(), d.getFullYear()].join('/');

let date = new Date();
let dd = date.getDate();//day of month
let mm = date.getMonth();// month
let yyyy = date.getFullYear();//day of week
if (dd < 10) {//if less then 10 add a leading zero
dd = "0" + dd;
}
if (mm < 10) {
mm = "0" + mm;//if less then 10 add a leading zero
}

function pad(value) {
return value.tostring().padstart(2, 0);
}
let d = new date();
console.log(d);
console.log(`${d.getfullyear()}-${pad(d.getmonth() + 1)}-${pad(d.getdate())}t${pad(d.gethours())}:${pad(d.getminutes())}:${pad(d.getseconds())}`);

You can use String.slice() which extracts a section of a string and returns it as a new string, without modifying the original string:
const currentDate = new Date().toISOString().slice(0, 10) // 2020-04-16
Or you can also use a lib such as Moment.js to format the date:
const moment = require("moment")
const currentDate = moment().format("YYYY-MM-DD") // 2020-04-16

A simple dateformat library saved my life (GitHub):
Node.js: var dateFormat = require("dateformat");
ES6: import dateFormat from "dateformat";
const now = new Date(); // consider 3rd of December 1993
const full = dateFormat(today, "yyyy-mm-dd"); // 1993-12-03
const day = dateFormat(today, "dd"); // 03
const month = dateFormat(today, "mm"); // 12
const year = dateFormat(today, "yyyy"); // 1993
It's worth to mention it supports a wide range of mask options.

Put clock forward by one hour [duplicate]

It amazes me that JavaScript's Date object does not implement an add function of any kind.
I simply want a function that can do this:
var now = Date.now();
var fourHoursLater = now.addHours(4);
function Date.prototype.addHours(h) {
// How do I implement this?
}
I would simply like some pointers in a direction.
Do I need to do string parsing?
Can I use setTime?
How about milliseconds?
Like this:
new Date(milliseconds + 4*3600*1000 /* 4 hours in ms */)?
This seems really hackish though - and does it even work?

JavaScript itself has terrible Date/Time API's. Nonetheless, you can do this in pure JavaScript:
Date.prototype.addHours = function(h) {
this.setTime(this.getTime() + (h*60*60*1000));
return this;
}

Date.prototype.addHours= function(h){
this.setHours(this.getHours()+h);
return this;
}
Test:
alert(new Date().addHours(4));

The below code will add 4 hours to a date (example, today's date):
var today = new Date();
today.setHours(today.getHours() + 4);
It will not cause an error if you try to add 4 to 23 (see the documentation):
If a parameter you specify is outside of the expected range, setHours() attempts to update the date information in the Date object accordingly

It is probably better to make the addHours method immutable by returning a copy of the Date object rather than mutating its parameter.
Date.prototype.addHours= function(h){
var copiedDate = new Date(this.getTime());
copiedDate.setHours(copiedDate.getHours()+h);
return copiedDate;
}
This way you can chain a bunch of method calls without worrying about state.

The version suggested by kennebec will fail when changing to or from DST, since it is the hour number that is set.
this.setUTCHours(this.getUTCHours()+h);
will add h hours to this independent of time system peculiarities.
Jason Harwig's method works as well.

Get a date exactly two hours from now, in one line.
You need to pass milliseconds to new Date.
let expiryDate = new Date(new Date().setHours(new Date().getHours() + 2));
or
let expiryDate2 = new Date(Date.now() + 2 * (60 * 60 * 1000) );
let nowDate = new Date();
let expiryDate = new Date(new Date().setHours(new Date().getHours() + 2));
let expiryDate2 = new Date(Date.now() + 2 * (60 * 60 * 1000) );
console.log('now', nowDate);
console.log('expiry', expiryDate);
console.log('expiry 2', expiryDate2);

You can use the Moment.js library.
var moment = require('moment');
foo = new moment(something).add(10, 'm').toDate();

I also think the original object should not be modified. So to save future manpower here's a combined solution based on Jason Harwig's and Tahir Hasan answers:
Date.prototype.addHours= function(h){
var copiedDate = new Date();
copiedDate.setTime(this.getTime() + (h*60*60*1000));
return copiedDate;
}

If you would like to do it in a more functional way (immutability) I would return a new date object instead of modifying the existing and I wouldn't alter the prototype but create a standalone function. Here is the example:
//JS
function addHoursToDate(date, hours) {
return new Date(new Date(date).setHours(date.getHours() + hours));
}
//TS
function addHoursToDate(date: Date, hours: number): Date {
return new Date(new Date(date).setHours(date.getHours() + hours));
}
let myDate = new Date();
console.log(myDate)
console.log(addHoursToDate(myDate,2))

There is an add in the Datejs library.
And here are the JavaScript date methods. kennebec wisely mentioned getHours() and setHours();

Check if it’s not already defined. Otherwise, define it in the Date prototype:
if (!Date.prototype.addHours) {
Date.prototype.addHours = function(h) {
this.setHours(this.getHours() + h);
return this;
};
}

This is an easy way to get an incremented or decremented data value.
const date = new Date()
const inc = 1000 * 60 * 60 // an hour
const dec = (1000 * 60 * 60) * -1 // an hour
const _date = new Date(date)
return new Date(_date.getTime() + inc)
return new Date(_date.getTime() + dec)

Another way to handle this is to convert the date to unixtime (epoch), then add the equivalent in (milli)seconds, then convert it back. This way you can handle day and month transitions, like adding 4 hours to 21, which should result in the next day, 01:00.

SPRBRN is correct. In order to account for the beginning/end of the month and year, you need to convert to Epoch and back.
Here's how you do that:
var milliseconds = 0; //amount of time from current date/time
var sec = 0; //(+): future
var min = 0; //(-): past
var hours = 2;
var days = 0;
var startDate = new Date(); //start date in local time (we'll use current time as an example)
var time = startDate.getTime(); //convert to milliseconds since epoch
//add time difference
var newTime = time + milliseconds + (1000*sec) + (1000*60*min) + (1000*60*60*hrs) + (1000*60*60*24*days);
var newDate = new Date(newTime); //convert back to date; in this example: 2 hours from right now
Or do it in one line (where variable names are the same as above:
var newDate =
new Date(startDate.getTime() + millisecond +
1000 * (sec + 60 * (min + 60 * (hours + 24 * days))));

For a simple add/subtract hour/minute function in JavaScript, try this:
function getTime (addHour, addMin){
addHour = (addHour ? addHour : 0);
addMin = (addMin ? addMin : 0);
var time = new Date(new Date().getTime());
var AM = true;
var ndble = 0;
var hours, newHour, overHour, newMin, overMin;
// Change form 24 to 12 hour clock
if(time.getHours() >= 13){
hours = time.getHours() - 12;
AM = (hours>=12 ? true : false);
}else{
hours = time.getHours();
AM = (hours>=12 ? false : true);
}
// Get the current minutes
var minutes = time.getMinutes();
// Set minute
if((minutes + addMin) >= 60 || (minutes + addMin) < 0){
overMin = (minutes + addMin) % 60;
overHour = Math.floor((minutes + addMin - Math.abs(overMin))/60);
if(overMin < 0){
overMin = overMin + 60;
overHour = overHour-Math.floor(overMin/60);
}
newMin = String((overMin<10 ? '0' : '') + overMin);
addHour = addHour + overHour;
}else{
newMin = minutes + addMin;
newMin = String((newMin<10 ? '0' : '') + newMin);
}
// Set hour
if((hours + addHour >= 13) || (hours + addHour <= 0)){
overHour = (hours + addHour) % 12;
ndble = Math.floor(Math.abs((hours + addHour)/12));
if(overHour <= 0){
newHour = overHour + 12;
if(overHour == 0){
ndble++;
}
}else{
if(overHour == 0){
newHour = 12;
ndble++;
}else{
ndble++;
newHour = overHour;
}
}
newHour = (newHour<10 ? '0' : '') + String(newHour);
AM = ((ndble + 1) % 2 === 0) ? AM : !AM;
}else{
AM = (hours + addHour == 12 ? !AM : AM);
newHour = String((Number(hours) + addHour < 10 ? '0': '') + (hours + addHour));
}
var am = (AM) ? 'AM' : 'PM';
return new Array(newHour, newMin, am);
};
This can be used without parameters to get the current time:
getTime();
Or with parameters to get the time with the added minutes/hours:
getTime(1, 30); // Adds 1.5 hours to current time
getTime(2); // Adds 2 hours to current time
getTime(0, 120); // Same as above
Even negative time works:
getTime(-1, -30); // Subtracts 1.5 hours from current time
This function returns an array of:
array([Hour], [Minute], [Meridian])

If you need it as a string, for example:
var defaultTime: new Date().getHours() + 1 + ":" + new Date().getMinutes();

I think this should do the trick
var nextHour = Date.now() + 1000 * 60 * 60;
console.log(nextHour)

You can even format the date in desired format using the moment function after adding 2 hours.
var time = moment(new Date(new Date().setHours(new Date().getHours() + 2))).format("YYYY-MM-DD");
console.log(time);

A little messy, but it works!
Given a date format like this: 2019-04-03T15:58
//Get the start date.
var start = $("#start_date").val();
//Split the date and time.
var startarray = start.split("T");
var date = startarray[0];
var time = startarray[1];
//Split the hours and minutes.
var timearray = time.split(":");
var hour = timearray[0];
var minute = timearray[1];
//Add an hour to the hour.
hour++;
//$("#end_date").val = start;
$("#end_date").val(""+date+"T"+hour+":"+minute+"");
Your output would be: 2019-04-03T16:58

The easiest way to do it is:
var d = new Date();
d = new Date(d.setHours(d.getHours() + 2));
It will add 2 hours to the current time.
The value of d = Sat Jan 30 2021 23:41:43 GMT+0500 (Pakistan Standard Time).
The value of d after adding 2 hours = Sun Jan 31 2021 01:41:43 GMT+0500 (Pakistan Standard Time).

How to show Your time and Our time clock using JavaScript?

On my website, I want to show my local time as Our Time and Visitor time as Your time. Now, I have this JS code:
<script>
function showTime(){
var date = new Date();
var h = date.getHours(); // 0 - 23
var m = date.getMinutes(); // 0 - 59
var s = date.getSeconds(); // 0 - 59
var session = "AM";
if(h == 0){
h = 12;
}
if(h > 12){
h = h - 12;
session = "PM";
}
h = (h < 10) ? "0" + h : h;
m = (m < 10) ? "0" + m : m;
s = (s < 10) ? "0" + s : s;
var time = h + ":" + m + ":" + s + " " + session;
document.getElementById("our_time").innerText = time;
document.getElementById("our_time").textContent = time;
setTimeout(showTime, 1000);
}
showTime();
</script>
It's showing my Local time.
Now, will I use same code to show the Visitor time or is there anything I need to change?

You need to know your timezone (a list of timezones can be found here) then use it with date.toLocaleTimeString() like this :
const locale = 'en-US';
const our_timeZone = 'America/Los_Angeles';
// refresh time every second
setInterval(() => {
document.getElementById('our_time').innerHTML = new Date().toLocaleTimeString(locale, { timeStyle: 'long', timeZone: our_timeZone });
document.getElementById('your_time').innerHTML = new Date().toLocaleTimeString(locale, { timeStyle: 'long' });
}, 1);
<p>Our time</p>
<span id="our_time"></span>
<p>Your time</p>
<span id="your_time"></span>

maybe your approach is wrong.
a) our time(website time): this should come from a server(and perhaps sync with it in a regular intervel )
b) your time(user's local time): new Date() will do this part since it runs on the client(browser).
this is a sample json data from "http://worldtimeapi.org/api/timezone/America/Argentina/Salta"
Oh! it's also free.. hook your ajax call with relevent timezone
{ "week_number":49, "utc_offset":"-03:00",
"utc_datetime":"2019-12-03T11:42:02.994093+00:00",
"unixtime":1575373322, "timezone":"America/Argentina/Salta",
"raw_offset":-10800, "dst_until":null, "dst_offset":0,
"dst_from":null, "dst":false, "day_of_year":337,
"day_of_week":2, "datetime":"2019-12-03T08:42:02.994093-03:00",
"client_ip":"hi hi hi... almost had me there", "abbreviation":"-03" }
also, try this piece of code..
new Date().toLocaleString('en-US', { hour: 'numeric', minute: 'numeric', hour12: true })
which will give an output
"5:23 PM"
ps: this is just a suggestion..

Get timezone of client using
const localDate = new Date(1489199400000);
localDate.getTimeZoneOffset();//time zone offset
then use this value in in Date and get the difference of your time and clients machine time

How to get current time in a format hh:mm AM/PM in Javascript?

I have a Javascript in which I need to paste the current time in a format HH:MM AM/PM. There's one catch - I need to put the time that starts in two hours from now, so for example, instead of 7:23PM I need to put 9:23PM, etc.
I tried to do something like: var dateFormat = new Date("hh:mm a") but it didn't work. I also tried to use:
var today = new Date();
var time = today.toLocaleTimeString().replace(/([\d]+:[\d]{2})(:[\d]{2})(.*)/, "$1$3")
alert(time);
but all I've seen was e.g. 18:23 instead of 6:23 PM (probably because of toLocaleTimeString() and my location in Europe) - maybe there's some unified way to do that that will work all around the World?. Also, I don't know exactly how to add the 2 hours to the final result. Can you help me?
Thanks!

You can convert the current time to 12 hour format with a one liner
new Date().toLocaleTimeString('en-US', { hour: 'numeric', hour12: true, minute: 'numeric' });
And to add two hours to your current time
Date.now() + 2 * 60 * 60 * 1000
So you can do it in a simple one line as:
new Date(Date.now() + 2 * 60 * 60 * 1000).toLocaleTimeString('en-US', { hour: 'numeric', hour12: true, minute: 'numeric' });

Use Date methods to set and retrieve time and construct a time string, something along the lines of the snippet.
[edit] Just for fun: added a more generic approach, using 2 Date.prototype extensions.
var now = new Date();
now.setHours(now.getHours()+2);
var isPM = now.getHours() >= 12;
var isMidday = now.getHours() == 12;
var result = document.querySelector('#result');
var time = [now.getHours() - (isPM && !isMidday ? 12 : 0),
now.getMinutes(),
now.getSeconds() || '00'].join(':') +
(isPM ? ' pm' : 'am');
result.innerHTML = 'the current time plus two hours = '+ time;
// a more generic approach: extend Date
Date.prototype.addTime = addTime;
Date.prototype.showTime = showTime;
result.innerHTML += '<h4>using Date.prototype extensions</h4>';
result.innerHTML += 'the current time plus twenty minutes = '+
new Date().addTime({minutes: 20}).showTime();
result.innerHTML += '<br>the current time plus one hour and twenty minutes = '+
new Date().addTime({hours: 1, minutes: 20}).showTime();
result.innerHTML += '<br>the current time <i>minus</i> two hours (format military) = '+
new Date().addTime({hours: -2}).showTime(true);
result.innerHTML += '<br>the current time plus ten minutes (format military) = '+
new Date().addTime({minutes: 10}).showTime(true);
function addTime(values) {
for (var l in values) {
var unit = l.substr(0,1).toUpperCase() + l.substr(1);
this['set' + unit](this['get' + unit]() + values[l]);
}
return this;
}
function showTime(military) {
var zeroPad = function () {
return this < 10 ? '0' + this : this;
};
if (military) {
return [ zeroPad.call(this.getHours()),
zeroPad.call(this.getMinutes()),
zeroPad.call(this.getSeconds()) ].join(':');
}
var isPM = this.getHours() >= 12;
var isMidday = this.getHours() == 12;
return time = [ zeroPad.call(this.getHours() - (isPM && !isMidday ? 12 : 0)),
zeroPad.call(this.getMinutes()),
zeroPad.call(this.getSeconds()) ].join(':') +
(isPM ? ' pm' : ' am');
}
<div id="result"></div>

Simply, you can do this
const date = new Date()
const options = {
hour: 'numeric',
minute: 'numeric',
hour12: true
};
const time = new Intl.DateTimeFormat('en-US', options).format(date)
console.log(time)
For more details, you can refer to the MDN docs regarding the same.

Note that the accepted answer, while good, does not appear to meet the format requirement of: HH:MM AM/PM. It returns midnight as "0:0:38am" and so forth.
There are many ways one could do this and one alternative is shown below. Click the "Run Code Snippet" to test.
<!DOCTYPE HTML>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>Clock</title>
</head>
<body>
<span id="clock" style="font-family: monospace; font-size: 48px; background-color: black; color: lime; padding: 10px;">00:00:00 AM</span>
<script type="text/javascript">
function getTime( ) {
var d = new Date( );
d.setHours( d.getHours() + 2 ); // offset from local time
var h = (d.getHours() % 12) || 12; // show midnight & noon as 12
return (
( h < 10 ? '0' : '') + h +
( d.getMinutes() < 10 ? ':0' : ':') + d.getMinutes() +
// optional seconds display
// ( d.getSeconds() < 10 ? ':0' : ':') + d.getSeconds() +
( d.getHours() < 12 ? ' AM' : ' PM' )
);
}
var clock = document.getElementById('clock');
setInterval( function() { clock.innerHTML = getTime(); }, 1000 );
</script>
</body>
</html>

Timestamp to human readable format

Well I have a strange problem while convert from unix timestamp to human representation using javascript
Here is timestamp
1301090400
This is my javascript
var date = new Date(timestamp * 1000);
var year = date.getFullYear();
var month = date.getMonth();
var day = date.getDay();
var hour = date.getHours();
var minute = date.getMinutes();
var seconds = date.getSeconds();
I expected results to be 2011 2, 25 22 00 00. But it is 2011, 2, 6, 0, 0, 0
What I miss ?

getDay() returns the day of the week. To get the date, use date.getDate(). getMonth() retrieves the month, but month is zero based, so using getMonth() + 1 should give you the right month. Time value seems to be ok here, albeit the hour is 23 here (GMT+1). If you want universal values, add UTC to the methods (e.g. date.getUTCFullYear(), date.getUTCHours())
const timestamp = 1301090400;
const date = new Date(timestamp * 1000);
const datevalues = [
date.getFullYear(),
date.getMonth()+1,
date.getDate(),
date.getHours(),
date.getMinutes(),
date.getSeconds(),
];
alert(datevalues); //=> [2011, 3, 25, 23, 0, 0]
Here is a small helper idea to retrieve values of a given Date:
const dateHelper = dateHelperFactory();
const formatMe = date => {
const vals = `yyyy,mm,dd,hh,mmi,ss,mms`.split(`,`);
const myDate = dateHelper(date).toArr(...vals);
return `${myDate.slice(0, 3).join(`/`)} ${
myDate.slice(3, 6).join(`:`)}.${
myDate.slice(-1)[0]}`;
};
// to a formatted date with zero padded values
console.log(formatMe(new Date(1301090400 * 1000)));
// the raw values
console.log(dateHelper(new Date(1301090400 * 1000)).values);
function dateHelperFactory() {
const padZero = (val, len = 2) => `${val}`.padStart(len, `0`);
const setValues = date => {
let vals = {
yyyy: date.getFullYear(),
m: date.getMonth()+1,
d: date.getDate(),
h: date.getHours(),
mi: date.getMinutes(),
s: date.getSeconds(),
ms: date.getMilliseconds(), };
Object.keys(vals).filter(k => k !== `yyyy`).forEach(k =>
vals[k[0]+k] = padZero(vals[k], k === `ms` && 3 || 2) );
return vals;
};
return date => ( {
values: setValues(date),
toArr(...items) { return items.map(i => this.values[i]); },
} );
}
.as-console-wrapper {
max-height: 100% !important;
}
Or see this small stackblitz project (a little bit more efficient).

var newDate = new Date();
newDate.setTime(unixtime*1000);
dateString = newDate.toUTCString();
Where unixtime is the time returned by your sql db. Here is a fiddle if it helps.
For example, using it for the current time:
document.write( new Date().toUTCString() );

here is kooilnc's answer w/ padded 0's
function getFormattedDate() {
var date = new Date();
var month = date.getMonth() + 1;
var day = date.getDate();
var hour = date.getHours();
var min = date.getMinutes();
var sec = date.getSeconds();
month = (month < 10 ? "0" : "") + month;
day = (day < 10 ? "0" : "") + day;
hour = (hour < 10 ? "0" : "") + hour;
min = (min < 10 ? "0" : "") + min;
sec = (sec < 10 ? "0" : "") + sec;
var str = date.getFullYear() + "-" + month + "-" + day + "_" + hour + ":" + min + ":" + sec;
/*alert(str);*/
return str;
}

use Date.prototype.toLocaleTimeString() as documented here
please note the locale example en-US in the url.

I was looking for a very specific solution for returning the current time as a guaranteed length string to prepend at the beginning of every log line. Here they are if someone else is looking for the same thing.
Basic Timestamp
"2021-05-26 06:46:33"
The following function returns a zero padded timestamp for the current time (always 19 characters long)
function getTimestamp () {
const pad = (n,s=2) => (`${new Array(s).fill(0)}${n}`).slice(-s);
const d = new Date();
return `${pad(d.getFullYear(),4)}-${pad(d.getMonth()+1)}-${pad(d.getDate())} ${pad(d.getHours())}:${pad(d.getMinutes())}:${pad(d.getSeconds())}`;
}
Full Timestamp
"2021-06-02 07:08:19.041"
The following function returns a zero padded timestamp for the current time including milliseconds (always 23 characters long)
function getFullTimestamp () {
const pad = (n,s=2) => (`${new Array(s).fill(0)}${n}`).slice(-s);
const d = new Date();
return `${pad(d.getFullYear(),4)}-${pad(d.getMonth()+1)}-${pad(d.getDate())} ${pad(d.getHours())}:${pad(d.getMinutes())}:${pad(d.getSeconds())}.${pad(d.getMilliseconds(),3)}`;
}

Hours, minutes and seconds depend on the time zone of your operating system. In GMT (UST) it's 22:00:00 but in different timezones it can be anything. So add the timezone offset to the time to create the GMT date:
var d = new Date();
date = new Date(timestamp*1000 + d.getTimezoneOffset() * 60000)

To direct get a readable local timezone:
var timestamp = 1301090400,
date = new Date(timestamp * 1000)
document.write( date.toLocaleString() );

I'm too late to the party since this question is already a decade old, but I want to provide a cleaner one without the use of any plugins like moment.js. only vanilla javascript.
export default {
// Accepts "1998-08-06 11:00:00" <-- This is UTC timestamp
getFormalDateTime(utcDate) {
const formattedUtc = utcDate.split(' ').join('T')+'Z'
let date = new Date(formattedUtc);
if (date.toString() === "Invalid Date")
return "N/A";
let dateString = date.toLocaleDateString("en-US", {month: 'long', day: 'numeric', year: 'numeric'});
let timeString = date.toLocaleTimeString("en-US", {hour: 'numeric', minute: 'numeric', hour12: true});
let formattedDate = dateString + " | " + timeString;
return formattedDate; // Returns "August 6, 1998 | 11:00 AM" <-- This is converted to client time zone.
},
// Accepts: "1998-08-06"
getFormalDate(convertDate) {
let date = new Date(convertDate);
if (date.toString() === "Invalid Date")
return "N/A";
let dateString = date.toLocaleDateString("en-US", {month: 'long', day: 'numeric', year: 'numeric'});
return dateString // Returns "August 6, 1998"
}
}
My code is formatted for ES6 modules because I use it as a module for my vuejs project but you can convert it to a normal javascript function.
getFormalDateTime('1998-08-06 11:00:00') the parameter should be in UTC time. This will return a formal date time converted to the client/browser timezone: August 6, 1998 | 11:00 AM
getFormalDate('1998-08-06') will just return August 6, 1998
More information here:
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/toLocaleDateString