我如何合并这个对象数组？

Question

I have this array of objects:

let array1 = [{
      id: 1,
      code: 'wawa'
    },
    {
      id: 2,
      code: 'qwqw'
    }]

    let array2 = [{
      id: 1,
      code: 'ewew'
    },
    {
      id: 3,
      code: 'eee'
    }]

    let array3 = [{
      id: 3,
      code: 'ww'
    },
    {
      id: 1,
      code: 'ww'
    },
    {
      id: 4,
      code: 'q'
    }
  ]

  let arrayGeral = new Array()
  arrayGeral.push(array1)
  arrayGeral.push(array2)
  arrayGeral.push(array3)

How i can merge the objects in the arrayGeral to a one array object?

I can do what i want using lodash, but i can't think in a way to iterate and make this automatic:

let merged = _.merge(_.keyBy(array1, 'id'), _.keyBy(array2, 'id'))
merged = _.merge(_.keyBy(merged, 'id'), _.keyBy(array3, 'id'))

Answer 1

I am assuming you want to merge them to 1 array without grouping by id. If that is the case you can use concat to merge them to 1 array like so: mergedArray = array1.concat(array2, array3)

 let array1 = [{ id: 1, code: 'wawa' }, { id: 2, code: 'qwqw' }] let array2 = [{ id: 1, code: 'ewew' }, { id: 3, code: 'eee' }] let array3 = [{ id: 3, code: 'ww' }, { id: 1, code: 'ww' }, { id: 4, code: 'q' } ] var concatArr = array1.concat(array2, array3); console.log(concatArr);

Answer 2

I suppose that the last values should be kept. If that's the case then you must inverse the way you push:

let arrayGeral = new Array();
arrayGeral.push(...array3);
arrayGeral.push(...array2);
arrayGeral.push(...array1);

Now all you have to do is to use the _.uniqBy lodash function:

_.uniqBy(arrayGeral, 'id');

 let array1 = [ { id: 1, code: 'wawa' }, { id: 2, code: 'qwqw' } ]; let array2 = [ { id: 1, code: 'ewew' }, { id: 3, code: 'eee' } ]; let array3 = [ { id: 3, code: 'ww' }, { id: 1, code: 'ww' }, { id: 4, code: 'q' } ]; let arrayGeral = new Array(); arrayGeral.push(...array3); arrayGeral.push(...array2); arrayGeral.push(...array1); console.log(_.uniqBy(arrayGeral, 'id'));

 <script src="https://cdn.jsdelivr.net/npm/lodash@4.17.15/lodash.min.js"></script>

Answer 3

If this is your output:

[                                                                   
   { id: 1, code: [ 'wawa', 'ewew', 'ww' ] },                          
   { id: 2, code: [ 'qwqw' ] },                                        
   { id: 3, code: [ 'eee', 'ww' ] },                                   
   { id: 4, code: [ 'q' ] }                                            
]                                                                     

Then refer to the below code:

 let array1 = [{ id: 1, code: 'wawa'}, { id: 2, code: 'qwqw' }] let array2 = [{ id: 1, code: 'ewew'}, { id: 3, code: 'eee' }] let array3 = [{ id: 3, code: 'ww' }, { id: 1, code: 'ww' }, { id: 4, code: 'q' }] var concated = array1.concat(array2).concat(array3); //Flaten the concatenated array let output = concated.reduce((acc, cur) => { let entry = acc.find(item => item.id === cur.id); if (entry && Array.isArray(entry.code)) { //Check if it has sth in the array entry.code.push(cur.code); } else { acc.push({id: cur.id, code: [cur.code]}); //For the 1st time, add it to the array } //console.log(acc); return acc; }, []); console.log(output);