function nextWeek(date) in JavaScript

Question

i am doing a javascript assessment concerning the class Date Here is the assessment: "Write the body of the nextWeek(date) function that returns a date 7 days after the date given in input" date is always a defined Date object.

So i wrote that code below:

function nextWeek(date){
var today=new Date();
var nextweek=new Date(today.getFullYear(),today.getMonth(),today.getDate()+7);
return nextweek;
}
var d=new Date();
console.log(d);
console.log(nextWeek(d));

And the result is :

"2021-04-25T15:02:16.234Z"

"2021-05-01T22:00:00.000Z"

for me it is correct because there is one week(7 days) long between "2021-04-25T15:02:16.234Z" and "2021-05-01T22:00:00.000Z"

But they told me that my code is wrong,i don't know what is wrong with it, Do you have any idea of what's wrong in that code above?

It isn't *wrong*, but it probably just doesn't do it the way they think it should be done. There are some issues: 1. Lack of indentation. 2. Using `var` (in modern JavaScript, always use `const` or `let`). 3. Creating a date to assign to `today` and then immediately overwriting it with a different value -- there's no reason for the first date you're creating. But the way you're moving forward seven days is just fine. Perhaps they don't understand that `Date` handles wrapping to the next month automatically. And kudos for returning a new `Date` rather than modifying the one you're given. — T.J. Crowder, Apr 25 '21 at 15:10
they said the solution doesn't work for the current date and another date and also they said my solution does not have to modify the input Date — bassey, Apr 25 '21 at 15:14
@bassey put your above comment in the actual question where it should have been all along, we aren't telepaths that knew what they thought was wrong — Dexygen, Apr 25 '21 at 15:27

KooiInc · Answer 1 · 2021-04-26T10:15:05.257

-1

That may be a one liner:

const now = new Date();
console.log(`now: ${now.toLocaleString()}`);
console.log(`a week from now: ${nextWeek4SomeDate(now).toLocaleString()}`);
console.log(`check: now is still now? ${now.toLocaleString()}`);

function nextWeek4SomeDate(date) { 
  return new Date(new Date(date).setDate(date.getDate() + 7));
//        |       |              └─ returns adjusted date as a number value
//        |       |                 i.e. the number of milliseconds between 
//        |       |                 1 January 1970 00:00:00 UTC and the given date
//        |       └─ create a new Date from the [date], so the original date is not modified          
//        └─ the number value from setDate should be reconverted to a real Date
}

edited Apr 26 '21 at 10:15

answered Apr 25 '21 at 15:24

KooiInc

104,388
28
131
164

Thanks,it works but i need to use a function rather than a const ,otherwise it is a good solution – bassey Apr 25 '21 at 15:36
It *is* a (n arrow) function (expression), but hey, now it's a [function declaration](https://stackoverflow.com/questions/336859/var-functionname-function-vs-function-functionname) – KooiInc Apr 25 '21 at 15:55

Jr Mendoza · Accepted Answer · 2021-04-25T15:23:41.527

-2

function nextWeek(date){
  var today=new Date(); // Remove this
  var nextweek=new Date(today.getFullYear(),today.getMonth(),today.getDate()+7); // Change today -> date
  return nextweek;
}
var d=new Date();
console.log(d);
console.log(nextWeek(d)); 

// Simple way of doing it.
function nextWeek(date) {
  date.setDate(date.getDate() + 7);
  return date;
}

edited Apr 25 '21 at 15:23

answered Apr 25 '21 at 15:18

Jr Mendoza

39
4

There are two function declarations in your answer. The last one is used (because it's hoisted). Furthermore, that function modifies the original date. – KooiInc Apr 25 '21 at 16:02
@KooiInc the second function was just an enhancement / refactored form of his existing code. It doesn't necessarily to be like that. I added a comment above it //Simple way of doing it – Jr Mendoza Apr 25 '21 at 16:08

function nextWeek(date) in JavaScript

2 Answers2