How to delete all elements from the array but retain specific element by value

Question

Good day guys! I have encounter some problem. I want to delete all the data from the array but doesn't delete that 1 data based from value.

example:

key = '2' 
array = [ 
         'data1': 'foo',
         'data' : 
                 {
                  'id' : '1', 
                  'id' : '2', 
                  'id' : '3'
                 }
         ]

result = [
          'data1': 'foo',
          'data' : 
                  {
                   'id' : '2'
                  }
         ]

that's all thank you

You can use `filter` method to do so. Please search on google before doing any type of questions. — Sifat Haque, Jun 09 '19 at 16:03
Possible duplicate of [How can I only keep items of an array that match a certain condition?](https://stackoverflow.com/questions/27131984/how-can-i-only-keep-items-of-an-array-that-match-a-certain-condition) — Nick is tired, Jun 09 '19 at 16:05

score 2 · Answer 1 · answered Jun 09 '19 at 16:00

2

You can use filter() and compare the value with key.

const key = 'foo';  
const array = ['foo', 'box', 'tree', 'bar'];
const result = array.filter(x => x === key);
console.log(result)

answered Jun 09 '19 at 16:00

Maheer Ali

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how about for nested arrays sir? – Jofeean Ogario Jun 09 '19 at 16:05
1

@JofeeanOgario Give some example by updating the question. – Maheer Ali Jun 09 '19 at 16:08
@JofeeanOgario Your data is not valid. You can't use `key:value` inside `[]`(arrays). – Maheer Ali Jun 09 '19 at 16:33
@JofeeanOgario And try it yourself first. And then again update the question with the code you have tried. Then ask me for help. – Maheer Ali Jun 09 '19 at 16:34

saurabh · Answer 2 · 2019-06-09T16:14:33.293

0

the simplest way will be to reassign the array or create a new array with the result

const key = 'foo';
let array = ['foo', 'box', 'tree', 'bar'];
/*array = new Array(key); //be carefull if yoy are using this and the key is singular numeric value*/
array = [key];
console.log(array);

edited Jun 09 '19 at 16:14

answered Jun 09 '19 at 16:04

saurabh

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1

Why `new Array(key)` whynot just `[key]` – Maheer Ali Jun 09 '19 at 16:09
Still its in correct it doesn't involve the elements of `array` anywhere. – Maheer Ali Jun 09 '19 at 16:17
it's not mentioned that key will not be in the array. And it also mentions `one data` for me it doesn't make sense to iterate through the array for that. – saurabh Jun 09 '19 at 16:22
OP said _"I want to delete all the data from the array but doesn't delete that 1 data based from value."_. – Maheer Ali Jun 09 '19 at 16:25

How to delete all elements from the array but retain specific element by value

2 Answers2