Javascript add leading zeroes to date


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"

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

You can define a "str_pad" function (as in php):

function str_pad(n) {
    return String("00" + n).slice(-2);
}

The new modern way to do this is to use toLocaleDateString, because it not just allows you to format a date with proper localization, you can even pass format options to archive the desired outcome:

var date = new Date(2018, 2, 1);
var result = date.toLocaleDateString("en-GB", { // you can skip the first argument
  year: "numeric",
  month: "2-digit",
  day: "2-digit",
});
console.log(result);

When you skip the first argument it will detect the browser language, instead. Additionally, you can use 2-digit on the year option, too.

If you don't need to support old browsers like IE10, this is the cleanest way to do the job. IE10 and lower versions won't understand the options argument.


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"

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
*/

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();

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


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.


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


Make your life easier and use Moment.js some sample code:

var beginDateTime = moment()
  .format('DD-MM-YYYY HH:mm')
  .toString();

// Now will print 30-06-2015 17:55
console.log(beginDateTime);

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);


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/


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)


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('/');

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}`);


 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
  }

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();
};

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