How to convert number to a date in javascript?

Question

i have to transform a number (0-364) to date starting from January 01, 2013. Example: 00 = Jan 01, 2013 or 45 = 15 Feb, 2013; 364= 31 Dec, 2013

Don't forget the leap year cases. – Bathsheba Jul 04 '13 at 11:28 — Bathsheba, Jul 04 '13 at 11:28

Tim Heap · Answer 1 · 2013-07-04T11:36:56.907

4

If you construct a new Date, but specify a day value that is too large, the day value will 'overflow' and increment the months. As such, you can do the following:

days = 1;
date = new Date(2013, 0, days);
// => Tue Jan 01 2013 00:00:00 GMT+1100 (EST)

days = 46;
date = new Date(2013, 0, days);
// => Fri Feb 15 2013 00:00:00 GMT+1100 (EST)

days = 365;
date = new Date(2013, 0, days);
// => Tue Dec 31 2013 00:00:00 GMT+1100 (EST)

Note that using this method, days starts from 1 for the start of the year. If you want days == 0 to produce 01 Jan, 2013, you will need to use: new Date(2013, 00, days + 1);

edited Jul 04 '13 at 11:36

answered Jul 04 '13 at 11:30

Tim Heap

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+1 nice .. you learn something new every day :-) – Manse Jul 04 '13 at 11:32
1

Perfect solution imo, just one note: the requested year was *2013*, but it doesn't matter a lot, moreover you should do `days + 1` or providing `0` as days will return in 31st of December of the previous year :) – Niccolò Campolungo Jul 04 '13 at 11:33
@LightStyle Good point, I updated my example to reflect 0 meaning 01-Jan – Tim Heap Jul 04 '13 at 11:35
i have try like this but my boss want only Feb 15 2013 – Alina Florea Hodoroaba Jul 04 '13 at 13:13

score 1 · Answer 2 · answered Jul 04 '13 at 11:29

1

Try something like this :

// initialize to start of the year
var dt= new Date(2013,00,01); 
// add the required number of days to date
dt.setDate(dt.getDate() + <number of days>);

where <number of days> is your variable

Working example here

answered Jul 04 '13 at 11:29

Manse

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i have try like this but my boss want only Feb 15 2013 – Alina Florea Hodoroaba Jul 04 '13 at 14:07
@AlinaFloreaHodoroaba then look at the documentation and work out for your self how to present the date how you require -> https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date – Manse Jul 04 '13 at 14:40

score 0 · Answer 3 · answered Jul 04 '13 at 11:30

0

You can use the getTime():

var days = xxx;
var date = new Date(2013, 0, 1);
var res = date.setTime(date.getTime() + (days * 24 * 60 * 60 * 1000));
console.log( new Date(res) );

answered Jul 04 '13 at 11:30

Sharon

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How to convert number to a date in javascript?

3 Answers3