get arrays which match using javascript

Question

I have two arrays.

The first Array:

let array1 = [
   {label:'john', value:1},
   {label:'susan', value:2},
   {label:'ann', value:3}
 ]

The second Array:

let array2 = [
 {id:1, name:'john', age:12},
 {id:3, name:'ann', age:24}
]

What am looking forward is to get all the array1 objects which value matches with id in array2

So basically the solution should have:

{label:'john', value:1}
{label:'ann', value:3}

So I have tried:

let matches  = [];
 array1.forEach((item1)=>{
   array2.forEach((item2)=>{
    if(item2.id === item1.value){
      matches.push() //stuck here 

   }
  })

})

Am stuck on how to push the items to a new array. Also looking at my code it looks abit messy. How do i refactor the code to work .

Do you want to match the value with the id only? Meaning, would {id:1, name:'hubert', age:99} in the second array still be considered a “match” for {label:'john', value:1} from the first? — C3roe
– C3roe, Commented Feb 2, 2018 at 12:34

Nina Scholz · Accepted Answer · 2018-02-02 12:55:30Z

4

You could filter array2 and take only the objects where value matches id in array2.

Methods:

Array#filter for filtering an array, retuns a new array with itmes where the callback returns a truthy value,
Array#find, which searches for an item, which meet the condition.
destructuring assignment, like { value } for getting only the property with that name.

var array1 = [{ label: 'john', value: 1 }, { label: 'susan', value: 2 }, { label: 'ann', value: 3 }],
    array2 = [{ id: 1, name: 'john', age: 12 }, { id: 3, name: 'ann', age: 24 }],
    result = array1.filter(({ value }) =>
        array2.find(({ id }) => 
            value === id
        )
    );
    
console.log(result);

edited Feb 2, 2018 at 12:55

answered Feb 2, 2018 at 12:31

Nina Scholz

388k26 gold badges367 silver badges417 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

xianshenglu Over a year ago

i think the readability is not good.Does that mean i am still not familiar with ES6? or the readability is truly not good

Mamun · Accepted Answer · 2018-02-02 12:45:19Z

2

Try the following:

let array1 = [
   {label:'john', value:1},
   {label:'susan', value:2},
   {label:'ann', value:3}
 ]

let array2 = [
 {id:1, name:'john', age:12},
 {id:3, name:'ann', age:24}
]
var matches = [];
array1.forEach(function(item1){
  array2.forEach(function(item2){
    if(item1.value == item2.id)
      matches.push(item1)
  });
});
console.log(matches);

edited Feb 2, 2018 at 12:45

answered Feb 2, 2018 at 12:35

Mamun

69k9 gold badges51 silver badges62 bronze badges

Collectives™ on Stack Overflow

get arrays which match using javascript

2 Answers 2

1 Comment

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

1 Comment

Comments

Your Answer

Sign up or log in

Post as a guest

Related