calculate the number of months between two dates, iterate a function on each month

Question

I'm needing to write a function that takes two dates (startDate, endDate) calculates the time between them in months or years (depending on an input). When the number of months or years is found, I need to iterate a loop that runs a very simple ajax call (I'm adding a record to Quickbase) for every month OR year between the start and end dates.

I've taken a couple of hacks at this but I'm running into trouble when I try to calculate months (due to the calendar dates (i.e. feb having 28 days etc)... I've calculated the time between the two dates in days, but I need months or years.

Any help would be appreciated!

None of the answers in the "original" post takes care of the 28th of february and so on, as the OP askes about.. — Nicolai Harbo, Aug 22 '17 at 10:02

score 5 · Accepted Answer · edited Sep 13 '16 at 02:23

5

just to start try

function Noofmonths(date1, date2) {
    var Nomonths;
    Nomonths= (date2.getFullYear() - date1.getFullYear()) * 12;
    Nomonths-= date1.getMonth() + 1;
    Nomonths+= date2.getMonth() +1; // we should add + 1 to get correct month number
    return Nomonths <= 0 ? 0 : Nomonths;
}

edited Sep 13 '16 at 02:23

Pankaj Anupam

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answered May 04 '14 at 18:57

Sajad Karuthedath

14,987
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This worked great on getting the months. Another question though. What if the start and end date don't have the same day of the month? I.e. startDate == 10-26-2004 && endDate == 10-16-2006? There is a remainder of days, and I'm lost as to what logic finds this. – Tabaker78 May 04 '14 at 20:07

score 1 · Answer 2 · answered May 04 '14 at 18:57

1

obtain date1 year and date2 year. get the difference and multiply by 12. obtain date1 month and date2 month. get the difference. add the differences together.

answered May 04 '14 at 18:57

SDMulroy

54
6

your answer is the description of my answer..!! – Sajad Karuthedath May 04 '14 at 19:00
why down vote. is that not mathematically a solution? :( – SDMulroy May 04 '14 at 19:00
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sorry i posted too slow. – SDMulroy May 04 '14 at 19:01
Somebody downvoted your answer and gone..!! – Sajad Karuthedath May 04 '14 at 19:02
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i don't care. moving on. – SDMulroy May 04 '14 at 19:03

calculate the number of months between two dates, iterate a function on each month

2 Answers2