Why am I getting incorrect number of days?

Asked Apr 25 '20 at 10:32

Active Apr 25 '20 at 10:41

Viewed 33 times

I am trying to get nr of days between two dates. But using this code found in several places, I get illogical numbers of days for certain dates. Why is this happening and how can I get expected nr of days?

const oneDay = 24 * 60 * 60 * 1000

getDays = (d2, d1) => {
  let days = Math.round(Math.abs((d2 - d1) / oneDay))
  return days
}

const d1 = new Date(1918, 4, 13)

let d2 = new Date(2020, 4, 30)
console.log(getDays(d2, d1)) //Ok, Expected: 37273, Actual: 37273

d2 = new Date(2020, 5, 1)
console.log(getDays(d2, d1)) //Nok, Expected: 37274, Actual: 37275

Happens even if const d1 = new Date(2020, 4, 30)

edited Apr 25 '20 at 10:38

asked Apr 25 '20 at 10:32

Suresh Subedi

3

The results are fine, your expectation is incorrect. The months start from zero, thus 4 is May, which has 31 days, and the 1th June is two days later than the 30th May. – Teemu Apr 25 '20 at 10:39
Please delete instead of answering – mplungjan Apr 25 '20 at 10:42
Also I recommend to create date at 15:00 to handle DST – mplungjan Apr 25 '20 at 10:43

Why am I getting incorrect number of days?

0 Answers0