How can i compare JsonString Date to Short Date

Question

I am trying to write a date compare function to see if the stored Data is up to date with what i am trying to import. To do so i need to compare my stored Sales date with the Date provided in a csv file. My stored Sales Date is in a the following format 2007-03-06T00:00:00.000Z and the date in my csv is 05/10/2019 I know i can try to extrct date from the jsonString but i am hoping there is a function which will allow me to do a simple compare. Below is a simple slice i used to make it work but there should be a better way

date1 = "2019-05-10T00:00:00.000Z" 
date2 = "05/10/2019"

newDate = date1.slice(5,7) +"/" + date1.slice(8,10) +"/" + date1.slice(0,4)
console.log(newDate)

if (newDate != date2){
  console.log("dates dont match")
}
else {
  console.log("We have latest sale")
}

Convert the strings to dates with [Converting a string to a date in JavaScript](https://stackoverflow.com/q/5619202/215552) then compare with [Compare two dates with JavaScript](https://stackoverflow.com/q/492994/215552) — Heretic Monkey, Apr 15 '20 at 20:57
Does this answer your question? [Compare two dates with JavaScript](https://stackoverflow.com/questions/492994/compare-two-dates-with-javascript) — Heretic Monkey, Apr 15 '20 at 21:03

score 2 · Answer 1 · answered Apr 15 '20 at 20:52

2

Convert into dates then compare on date string.

date1 = "2019-05-10T00:00:00.000Z" 
date2 = "05/10/2019"
const d1 = new Date(date1)
const d2 = new Date(date2)
d1.toLocaleDateString() == d2.toLocaleDateString()

answered Apr 15 '20 at 20:52

zavr

2,049
2
18
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2

Note that `new Date(string)` is not guaranteed to function the same on all platforms with any format other than ISO 8601... – Heretic Monkey Apr 15 '20 at 20:54
1

date1 local date string returns 5/9 if you are west of GMT (e.g. north and south america) – Ctznkane525 Apr 15 '20 at 20:55
1

Once you have `Date` objects, just use `d1.valueOf() === d2.valueOf()` – Heretic Monkey Apr 15 '20 at 21:02
@HereticMonkey please don't use === when not needed. it's heresy :D – zavr Apr 15 '20 at 21:39

score 0 · Answer 2 · answered Apr 15 '20 at 20:53

0

What you are doing is comparing strings, not dates. You can use moment to convert strings to dates and compare date values

answered Apr 15 '20 at 20:53

Nonik

645
4
11

Ctznkane525 · Answer 3 · 2020-04-15T21:03:12.223

0

You need dates, but probably have to strip the time FOR date1 too for those of us that aren't in GMT:

date1 = "2019-05-10T00:00:00.000Z" 
date2 = "05/10/2019"
const d1 = new Date(date1.slice(5,7) +"/" + date1.slice(8,10) +"/" + date1.slice(0,4))
const d2 = new Date(date2)

if (d1.valueOf() != d2.valueOf()){
  console.log("dates dont match")
}
else {
  console.log("We have latest sale")
}

edited Apr 15 '20 at 21:03

answered Apr 15 '20 at 20:59

Ctznkane525

7,297
3
16
40

Once you have `Date` objects, just use `d1.valueOf() === d2.valueOf()`. Not sure why people are bothering with `toLocaleDateString`... – Heretic Monkey Apr 15 '20 at 21:02
I changed it just for you :-) @HereticMonkey – Ctznkane525 Apr 15 '20 at 21:04

How can i compare JsonString Date to Short Date

3 Answers3