CODEWITHSUNDEEP
javascriptarraysname-value
user3084017
user3084017

Reputation: 177

Convert an array to an array of objects

How I can convert an array to an array of JavaScript objects.

For example I have an array as 

data = [
    ["fruits","frozen","fresh","rotten"],
    ["apples",884,494,494],
    ["oranges",4848,494,4949],
    ["kiwi",848,33,33]
]

I want to convert it to a name value pair.

For example, first object in the resulting collection would be

 {"fruits": "apple", "frozen": 884, "fresh": 494, "rotten": 494}

and so on for rest of the data.

Upvotes: 15

Views: 59730

Answers (4)

mplungjan
mplungjan

Reputation: 177860

Destructing: 

const data = [
    ["fruits","frozen","fresh","rotten"],
    ["apples",884,494,494],
    ["oranges",4848,494,4949],
    ["kiwi",848,33,33]
]
const titles = data[0]
const obj = data.slice(1).map(([fruits,frozen,fresh,rotten]) => ({ fruits,frozen,fresh,rotten }) )
console.log(obj)

Upvotes: 4

Christian Landgren
Christian Landgren

Reputation: 13763

If you use both map and reduce, the solution becomes very elegant:

var collection = [
    ["fruits","frozen","fresh","rotten"],
    ["apples",884,494,494],
    ["oranges",4848,494,4949],
    ["kiwi",848,33,33]
];

var keys = collection.shift();
collection = collection.map(function (row) {
    return keys.reduce(function (obj, key, i) {
      obj[key] = row[i];
      return obj;
    }, {});
});

Output:

[ 
  { fruits: 'apples', frozen: 884, fresh: 494, rotten: 494 },
  { fruits: 'oranges', frozen: 4848, fresh: 494, rotten: 4949 },
  { fruits: 'kiwi', frozen: 848, fresh: 33, rotten: 33 } 
]

Upvotes: 8

Pavlo
Pavlo

Reputation: 44899

One can avoid iterating twice using shift() + map() + forEach():

var data = [
    ["fruits","frozen","fresh","rotten"],
    ["apples",884,494,494],
    ["oranges",4848,494,4949],
    ["kiwi",848,33,33]
];

var collection = data.slice(); // make a copy
var keys = collection.shift();

collection = collection.map(function (e) {
    var obj = {};

    keys.forEach(function (key, i) {
        obj[key] = e[i];
    });

    return obj;
});

Demo: http://jsfiddle.net/d7W76/2/

Upvotes: 6

crush
crush

Reputation: 17013

DEMO

Using your supplied data:

var data = [
    ["fruits","frozen","fresh","rotten"],
    ["apples",884,494,494],
    ["oranges",4848,494,4949],
    ["kiwi",848,33,33]
]

The following function will treat the first element of the array as the keys for the objects properties. It will then loop over the remaining elements, and convert them into an object using these keys. Finally, it will return an array of these new objects.

function convertToArrayOfObjects(data) {
    var keys = data.shift(),
        i = 0, k = 0,
        obj = null,
        output = [];

    for (i = 0; i < data.length; i++) {
        obj = {};

        for (k = 0; k < keys.length; k++) {
            obj[keys[k]] = data[i][k];
        }

        output.push(obj);
    }

    return output;
}

Output

[
    { fruits: 'apples', fresh: 494, frozen: 884, rotten: 494 },
    { fruits: 'oranges', fresh: 494, frozen: 4848, rotten: 4949 },
    { fruits: 'kiwi', fresh: 33, frozen: 848, rotten: 33 }
]

Upvotes: 10

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