How to check if key of object in array has specific value in javascript

Question

Is it possible to check if an object in an array has a specific Date value in the following data format?

I have an array like this for example

[
  {
    date: '2020-05-03',
    items: [{}...]
  },
  ...
]

-> In the above array, I want to check if any object in the array has '2020-05-03' as the date value.

And I want to find out if an object with Date is ??

I tried the following, but this only confirms that it has a 'date' as the key, and I couldn't compare values.

const existsDate = _.find(prev, 'date');

I also want to push an item to the items of the object containing that date if a date already exists.

If not, i need to create a new date object.

What have you already tried? It's a good idea to include what you've already tried doing to overcome this, and what problems you're facing. This will make your question more focused and easier to answer concisely. Please take the [Tour](//stackoverflow.com/tour) and review [How do I ask a good question?](//stackoverflow.com/help/how-to-ask). — Tad Wohlrapp, May 03 '20 at 15:47
Does this answer your question? [How do I check if an array includes a value in JavaScript?](https://stackoverflow.com/questions/237104/how-do-i-check-if-an-array-includes-a-value-in-javascript) — alexortizl, May 03 '20 at 15:51

Shubham Khatri · Answer 1 · 2020-05-03T15:56:10.407

0

You can make use of Array.prototype.find and do a string comparison

var arr = [
  {
    date: '2020-05-03',
    items: [{}...]
  },
]

const obj = arr.find(item => item.data === '2020-05-03');

EDIT: Since you want to update the existing array, you would need to make use of slice with findIndex to update array

var arr = [
      {
        date: '2020-05-03',
        items: [{}...]
      },
    ]
    const newItem = {};
    const index= arr.findIndex(item => item.data === '2020-05-03');
    if(index > -1) {
       arr = [...arr.slice(0, index), {...arr[index], items: arr[index].items.concat(newItems), ...arr.slice(index + 1)}
    } else {
      arr.push({data: new Date(), items: [newItem]})
    }

edited May 03 '20 at 15:56

answered May 03 '20 at 15:47

Shubham Khatri

270,417
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406
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I registered additional questions with my attempts. Thank you for checking! – COLEAN May 03 '20 at 15:51
@COLEAN Updated myanswer for your requirements – Shubham Khatri May 03 '20 at 15:56

Ashish Ranjan · Answer 2 · 2020-05-03T15:59:46.617

0

You can use, Array find(), some() to get/check the required conditions, for example:

const arr = [
  {
    date: '2020-05-03',
    items: [{}]
  },
  {
    date: '2020-05-02',
    items: [{}]
  }
]

function checkAndAdd(date) {
  const res = arr.find(ob => ob.date === date);
  // console.log(res);
  // based on the added comments.
  // if date is found, push something to the items, list:
  if (res) {
    res.items.push('Hello');
  } else {
    arr.push({
      date,
      items: [{}]
    })
  }
  
  console.log('finalArray', arr);

}

checkAndAdd('2020-05-03');
checkAndAdd('2020-05-06');

edited May 03 '20 at 15:59

answered May 03 '20 at 15:48

Ashish Ranjan

12,760
5
27
51

I registered additional questions with my attempts. Thank you for checking! – COLEAN May 03 '20 at 15:51
@COLEAN Your question isn't much clear to me, can you try reframing ut? – Ashish Ranjan May 03 '20 at 15:53
@COLEAN: Updated the answer, as far as I understood the requirement. – Ashish Ranjan May 03 '20 at 16:00

score 0 · Answer 3 · answered May 03 '20 at 15:49

0

you caan use filter or find function

let arr = [
    {data:'2020-05-23'},
    {data:'2020-06-23'},
    {data:'2020-07-23'}
]

let find = arr.find( (val) => val.data == '2020-06-23')

console.log(find)

answered May 03 '20 at 15:49

Khairu Aqsara

1,321
3
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I registered additional questions with my attempts. Thank you for checking! – COLEAN May 03 '20 at 15:51

score 0 · Answer 4 · answered May 03 '20 at 16:01

I'm not sure what exactly you are looking to do but his code iterates through the array of objects and checks against the date variable. It outputs the index (i).

let date = "2020-05-03"

const array = [

{   date: "2020-05-01"   },   
{   date: "2020-05-02"   },   
{   date: "2020-05-03",   }, 

]


for(let i = 0 ; i < array.length ; i ++) {   
    if(array[i].date === date) {
        console.log(i);   } 
    else {
        console.log("Date not in array");   
    } 
}

How to check if key of object in array has specific value in javascript

4 Answers4