Making an array of object a value of a object in Array in Node.js

Question

I have two arrays of objects. example

 data1 = [{
     foo: '2',
     box: 'yes',
     id: '1234'
 }, {
     foo: '34',
     box: 'no',
     id: '1235'
 }];

 data2 = [{
     key: 'value',
     key: 'value',
     id: '1234'
 }, {
     key: 'value',
     key: 'value',
     id: '1235'
 }];

I need it like this based on matching id value : each obj has a unique key id, that much the second array.

finalData = [{
    foo: '2',
    box: 'yes',
    id: '1234',
    key: 'value',
    key: 'value'
}, {
    box: '34',
    box: 'no',
    id: '1235',
    key: 'value',
    key: 'value'
}];

basically merging the two arrays of objects based on key id .

Answer 1

Use Object.assign for this so that you can combine the array with the common id value, use find having condition that compares the id of both the objects.

var data1 =[ {foo:'2',box:'yes',id:'1234'},{foo:'34',box:'no',id:'1235'} ]; 
var data2 =[{key:'value',key2:'value2', id:'1234'},{key:'value',key2:'value2', id:'1235'}];

data1.map(x => Object.assign(x, data2.find(y => y.id == x.id)));

console.log(data1);

Since you have same key name multiple times which is ignored by the JSON object so I have taken a new property name key2 for this example.

Answer 2

building on @Ankit answer, you can use the spread operator too !! something like this

var data1 =[ {foo:'2',box:'yes',id:'1234'},{foo:'34',box:'no',id:'1235'} ]; 
var data2 =[{key:'value',key2:'value2', id:'1234'},{key:'value',key2:'value2', id:'1235'}];

const arr = data1.map(x => ({ ...x, ...data2.find(y => y.id == x.id)}));

console.log(arr);