Javascript Determine 10 days before specific date

Question

So I am currently fetching some records from my database, and one of the records is a 'last edited' which is a date. However, I just want to display this 10 days before it has been exactly one year since the specific date. How would I approach this? I know how to deal with arrays and the fetching itself, but I'm not sure how I would deal with the date?

This is what I've done so far:

var startDate = fetchedDate;
var validDate = new Date(startDate);
var fullYear = validDate.getFullYear();
validDate.setFullYear(fullYear + 1);

And then I need to create a new date to compare it, I suppose? But how? I also want to know how many days it is until it has been one year.

use [momentjs](https://momentjs.com/) for dates, makes it easy — baao, Apr 01 '18 at 19:50
@JonasW. I use Firebase. But that's not really my concern, what I'm wondering is how I would use 'if else' - in my criteria. — askaale, Apr 01 '18 at 19:51

Miguel Angel · Answer 1 · 2018-04-01T20:34:01.950

0

If you wanna make it with pure javascript you can

var startDate = fetchedDate;
var validDate = new Date(startDate);
validDate.setYear(validDate.getFullYear() - 1);
validDate.setDate(validDate.getDate() - 10);

But I also will recommend you to use moment.js, is a very good javascript library to handle dates, otherwise sometimes is like trying to reinvent the wheel.

edited Apr 01 '18 at 20:34

answered Apr 01 '18 at 20:06

Miguel Angel

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should be validDate in line 3 instead of myDate – ecg8 Apr 01 '18 at 20:13
You're right, thanks!! – Miguel Angel Apr 01 '18 at 20:17
Also, getYear is deprecated, use getFullYear – ecg8 Apr 01 '18 at 20:20
I would strongly advise to rely on momentjs only, as manipulating dates is always tricky because of all the edge cases. You can find many articles on the subject (google "date manipulation edge cases"). – grandouassou Apr 01 '18 at 20:32

Javascript Determine 10 days before specific date

1 Answers1