[javascript] Add one day to date in javascript

I am sure that a lot of people asked this question but when I checked the answers it seems to me that they are wrong that what I found

var startDate = new Date(Date.parse(startdate));
//The start date is right lets say it is 'Mon Jun 30 2014 00:00:00'

var endDate = new Date(startDate.getDate() + 1);
// the enddate in the console will be 'Wed Dec 31 1969 18:00:00' and that's wrong it should be  1 july 

I know that .getDate() return from 1-31 but Does the browser or the javascript increase only the day without updating the month and the year ?

and in this case Should I write an algorithm to handle this ? or there is another way ?

var datatoday = new Date();
var datatodays = datatoday.setDate(new Date(datatoday).getDate() + 1);
todate = new Date(datatodays);
console.log(todate);

This will help you...

Just for the sake of adding functions to the Date prototype:

In a mutable fashion / style:

Date.prototype.addDays = function(n) {
   this.setDate(this.getDate() + n);
};

// Can call it tomorrow if you want
Date.prototype.nextDay = function() {
   this.addDays(1);
};

Date.prototype.addMonths = function(n) {
   this.setMonth(this.getMonth() + n);
};

Date.prototype.addYears = function(n) {
   this.setFullYear(this.getFullYear() + n);
}

// etc...

var currentDate = new Date();
currentDate.nextDay();

I think what you are looking for is:

startDate.setDate(startDate.getDate() + 1);

Also, you can have a look at Moment.js

A javascript date library for parsing, validating, manipulating, and formatting dates.

use this i think it is useful for you

var endDate=startDate.setDate(startDate.getDate() + 1);

There is issue of 31st and 28th Feb with getDate() I use this function getTime and 24*60*60*1000 = 86400000

var dateWith31 = new Date("2017-08-31");_x000D_
var dateWith29 = new Date("2016-02-29");_x000D_
_x000D_
var amountToIncreaseWith = 1; //Edit this number to required input_x000D_
_x000D_
console.log(incrementDate(dateWith31,amountToIncreaseWith));_x000D_
console.log(incrementDate(dateWith29,amountToIncreaseWith));_x000D_
_x000D_
function incrementDate(dateInput,increment) {_x000D_
        var dateFormatTotime = new Date(dateInput);_x000D_
        var increasedDate = new Date(dateFormatTotime.getTime() +(increment *86400000));_x000D_
        return increasedDate;_x000D_
    }

If you don't mind using a library, DateJS (https://github.com/abritinthebay/datejs/) would make this fairly easy. You would probably be better off with one of the answers using vanilla JavaScript however, unless you're going to take advantage of some other DateJS features like parsing of unusually-formatted dates.

If you're using DateJS a line like this should do the trick:

Date.parse(startdate).add(1).days();

You could also use MomentJS which has similar features (http://momentjs.com/), however I'm not as familiar with it.

The Date constructor that takes a single number is expecting the number of milliseconds since December 31st, 1969.

Date.getDate() returns the day index for the current date object. In your example, the day is 30. The final expression is 31, therefore it's returning 31 milliseconds after December 31st, 1969.

A simple solution using your existing approach is to use Date.getTime() instead. Then, add a days worth of milliseconds instead of 1.

For example,

var dateString = 'Mon Jun 30 2014 00:00:00';

var startDate = new Date(dateString);

// seconds * minutes * hours * milliseconds = 1 day 
var day = 60 * 60 * 24 * 1000;

var endDate = new Date(startDate.getTime() + day);

JSFiddle

Please note that this solution doesn't handle edge cases related to daylight savings, leap years, etc. It is always a more cost effective approach to instead, use a mature open source library like moment.js to handle everything.