CODEWITHSUNDEEP
javascriptarraysarray-merge
Fahmi Salmin
Fahmi Salmin

Reputation: 25

how to merge the value or index in array

how to merge the value or merge the index,
for example I have :

var input = [
            ["0001", "Roman Alamsyah", "Bandar Lampung", "21/05/1989", "Membaca"],
            ["0002", "Dika Sembiring", "Medan", "10/10/1992", "Bermain Gitar"],      
        ];

and I want my array to be

var output = [
            ["0001", "Roman Alamsyah", "Bandar Lampung 21/05/1989", "Membaca"],
            ["0002", "Dika Sembiring", "Medan 10/10/1992", "Bermain Gitar"]
        ];

thanks

Upvotes: 2

Views: 146

Answers (3)

Blauharley
Blauharley

Reputation: 4246

You might use destructuring assignment :

[a,b,c,d] = [1,2,3,4];
var mergedArr = [a,+(""+b+c),d];

console.log(mergedArr);

In this way you can treat each array-element as variable at a certain index. After that you can merge each variable as you like.

It must be mentioned that this operator is not supported by all browsers yet.

Addition to updated question:

You can also implement a function that recursively merges array-elements at a given start- and end-index. In this resurive way you can merge sub-arrays as well. 

var input = [
  ['0001',
  'Roman Alamsyah',
  'Bandar Lampung',
  '21/05/1989',
  'Membaca'],
  [
    '0002',
    'Dika Sembiring',
    'Medan',
    '10/10/1992',
    'Bermain Gitar'
  ],
];
  
var input2 = [
  [
    ['0001',
     'Roman Alamsyah',
     'Bandar Lampung',
     '21/05/1989',
     'Membaca']
  ],
  [
  '0002',
  'Dika Sembiring',
  'Medan',
  '10/10/1992',
  'Bermain Gitar'
  ],
];

function mergeValues(arr, start, end) {
  if (arr.__proto__.constructor === Array && arr[0].__proto__.constructor !== Array) {
    var mergedValues = [];
    var result = [];
    arr.forEach(function (value, index) {
      if (index < start) result.push(value);
       else if (index > end) {
        if (mergedValues.length) {
          result.push(mergedValues.join(' '));
          mergedValues = [];
        }
        result.push(value);
      } 
      else mergedValues.push(value);
    });
    return result;
  } 
  else {
    return arr.map(function (subarr) {
      return mergeValues(subarr, start, end);
    });
  }
}

console.log("input: ",mergeValues(input, 2, 3));
console.log("input2: ",mergeValues(input2, 2, 3));

Hope this helps.

Upvotes: 1

Nina Scholz
Nina Scholz

Reputation: 386560

You could specify the index joinAt, where the next two elements has to be joined and then splice the array with a new string of the spliced parts.

var array = [
        ["0001", "Roman Alamsyah", "Bandar Lampung", "21/05/1989", "Membaca"],
        ["0002", "Dika Sembiring", "Medan", "10/10/1992", "Bermain Gitar"],
    ],
    joinAt = 2;

array.forEach(function (a) {
    a.splice(joinAt, 0, a.splice(joinAt, 2).join(' '));
});

console.log(array);
.as-console-wrapper { max-height: 100% !important; top: 0; }

Upvotes: 0

rvrabbit
rvrabbit

Reputation: 347

Not sure if this is what you want, but it produces the output asked for in the question:

[1,2,3,4].reduce(
    (accumulator, currentValue, currentIndex, array) => {
        (currentIndex !== 1 && currentIndex !== 2)
            ? accumulator.push(currentValue)
            : currentIndex === 1
                ? accumulator.push(
                    Number.parseInt(
                        array[currentIndex].toString()
                        + array[currentIndex + 1].toString()
                    )
                )
                : undefined ;
        return accumulator ;
    }
    , []
)

See: Array.prototype.reduce() on MDN

Upvotes: 0

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