sort object by key by using lodash but key has lost after sorted

Question

I want to sort some Object look likes this

data = {
        "imH3i4igFNxM3GL": {
            "name": "Nacky",
            "age": 12
        },
        "vuzPuZUmyT8Z5nE": {
            "name": "Emmy",
            "age": 20
        },
        "OkIPDY1nGjxlq3W": {
            "name": "Nat",
            "age": 20
        }
}

I want to sort it by "name". I tried to use Lodash for this problem.

_.sortBy(data, [function(o) { return o.name; }]);

but, it return me an array of objects without the keys

[
    {
      "name": "Emmy",
      "age": 20
    },
    {
      "name": "Nacky",
      "age": 12
    },
    {
      "name": "Nat",
      "age": 20
    }
]

I want it return me sorted object with key like the same

{
    "vuzPuZUmyT8Z5nE": {
        "name": "Emmy",
        "age": 20
    },
    "imH3i4igFNxM3GL": {
        "name": "Nacky",
        "age": 12
    },
    "OkIPDY1nGjxlq3W": {
        "name": "Nat",
        "age": 20
    }
}

what should I do? thanks

You're not sorting an array; you're trying to sort an object. This is generally a bad idea, since iterating over the object is not guaranteed to output the keys in the order you want [see this comment on a similar question](http://stackoverflow.com/questions/1069666/sorting-javascript-object-by-property-value#comment67886877_1069666) — Heretic Monkey, May 08 '17 at 16:42
Well, `_.sortBy` accepts an object but will return an array, as per the doc. As Mike says, you cannot get an object with "sorted" keys. — Hugues M., May 08 '17 at 16:45

Ori Drori · Answer 1 · 2017-05-08T20:08:05.873

Objects in JS can't be sorted, and the order of the properties is not reliable, ie it depends on browsers' implementations. That's why _.sortBy() is converting your object into a sorted array.

I can think of 2 options to work with that.

Add the key to the objects in the array

If you just need an ordered array with the keys in the objects, so you can render a list.

var data = {
        "imH3i4igFNxM3GL": {
            "name": "Nacky",
            "age": 12
        },
        "vuzPuZUmyT8Z5nE": {
            "name": "Emmy",
            "age": 20
        },
        "OkIPDY1nGjxlq3W": {
            "name": "Nat",
            "age": 20
        }
};

var result = _(data)
  .map(function(v, k) { // insert the key into the object
    return _.merge({}, v, { key: k });
  })
  .sortBy('name') // sort by name
  .value();
  
console.log(result);

<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.4/lodash.min.js"></script>

Create an order array

Create an array of ordered keys, and use them when you wish to render the objects in order.

var data = {
        "imH3i4igFNxM3GL": {
            "name": "Nacky",
            "age": 12
        },
        "vuzPuZUmyT8Z5nE": {
            "name": "Emmy",
            "age": 20
        },
        "OkIPDY1nGjxlq3W": {
            "name": "Nat",
            "age": 20
        }
};

var orderArray = _(data)
  .keys() // create an array of keys
  .sortBy(function(key) { // sort the array using the original names
    return data[key].name;
  }) // sort by name
  .value();

console.log('The order array', orderArray);

console.log(orderArray.map(function(k) {
  return data[k];
}));

<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.4/lodash.min.js"></script>

score 0 · Answer 2 · answered Jan 07 '19 at 11:47

0

I use something like this.

    let data = {
    'g34ghgj3kj': {
        YOUR_KEY: 'g34ghgj3kj',
        'key1': false,
        'key2': false,
    },
    'hh334h664': {
        YOUR_KEY: 'hh334h664',
        'key1': true,
        'key2': false,
    },
    //{...}
};

_.orderBy(data, ['key1', 'key2'], ['desc', 'desc']).reduce((result, value) => {
    result[value.YOUR_KEY] = value;
    return result;
}, {});

answered Jan 07 '19 at 11:47

Ilya Degtyarenko

1,359
8
16

Unfortunately, this method results in redundant data and requires the key to be in the objects. – Daniel J. Lewis Nov 05 '20 at 02:13

sort object by key by using lodash but key has lost after sorted

2 Answers2