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I have an array of objects, let's say:

var objects = [
  {name: 'A'},
  {name: '1'},
  {name: 'B'}
]

Knowing that I can sort it using Lodash sortBy:

objects= _.sortBy(objects, 'name')

which will result in this:

[
  {name: '1'},
  {name: 'A'},
  {name: 'B'}
]

But my desired output is this:

[
  {name: 'A'},
  {name: 'B'},
  {name: '1'}
]

Please help.

I have an array of objects, let's say:

var objects = [
  {name: 'A'},
  {name: '1'},
  {name: 'B'}
]

Knowing that I can sort it using Lodash sortBy:

objects= _.sortBy(objects, 'name')

which will result in this:

[
  {name: '1'},
  {name: 'A'},
  {name: 'B'}
]

But my desired output is this:

[
  {name: 'A'},
  {name: 'B'},
  {name: '1'}
]

Please help.

• javascript
• arrays
• string
• sorting
• lodash

Share Improve this question Follow edited Dec 27, 2016 at 6:35 user663031 asked Dec 27, 2016 at 2:55 Zhi RuiZhi Rui 1,06311 gold badge1111 silver badges1010 bronze badges 9

• @TrojanByAccident Yes what do you mean by same key? They are three different objects. And I'd showed what I have tried using Lodash soryBy, what do you mean by 'put some effort into it' when I posted what I have tried? Flagging your ment. – Zhi Rui Commented Dec 27, 2016 at 3:00
• What's the possible range of characters? Only A-Z and 0-9? – Robby Cornelissen Commented Dec 27, 2016 at 3:01
• @RobbyCornelissen Yes sir. – Zhi Rui Commented Dec 27, 2016 at 3:02
• 1 @user1422866 That's not exactly showing what you have tried. That's saying that you know something else doesn't give you the desired results, but you aren't showing any code of your own that attempts to achieve that result. – TrojanByAccident Commented Dec 27, 2016 at 3:02
• 1 When sorting the values AA and A1, which do you expect to e first? I.e., do your sorting rules only apply to the first character or also to subsequent characters? – Robby Cornelissen Commented Dec 27, 2016 at 4:35

 |  Show 4 more ments

5 Answers 5

Sorted by: Reset to default 6

Using Array#sort you can apply this logic:

// If both are numbers or both are not numbers
isNaN(a.name) === isNaN(b.name) ?
     // then pare between them 
    a.name.localeCompare(b.name)
    : // else
    // If the 1st is not a number move it up, if it's a number move it down
    (isNaN(a.name) ? -1 : 1); 

Without lodash:

var objects = [{"name":"A"},{"name":"3"},{"name":"1"},{"name":"B"}];

objects.sort(function(a, b) {
  return isNaN(a.name) === isNaN(b.name) ? a.name.localeCompare(b.name) : (isNaN(a.name) ? -1 : 1);
});

console.log(objects);

As part of a lodash's chain:

var objects = [{"name":"A"},{"name":"3"},{"name":"1"},{"name":"B"}];

var result = _(objects)
  .sort(function(a, b) {
    return isNaN(a.name) === isNaN(b.name) ? a.name.localeCompare(b.name) : (isNaN(a.name) ? -1 : 1);
  }) 
  .value();

console.log(result);

<script src="https://cdnjs.cloudflare./ajax/libs/lodash.js/4.17.3/lodash.min.js"></script>

I'm not sure if using lodash's sortBy is the correct approach for this problem. Here's an implementation using Javascript's Array#sort method.

It takes not only the first character but the entire string into account when doing the sorting.

const objects = [{
  name: '2'
}, {
  name: 'B'
}, {
  name: '1'
}, {
  name: 'A'
}, {
  name: 'A1'
}, {
  name: 'AA'
}]

objects.sort((o1, o2) => {
  let a = o1.name, b = o2.name;
  let isDigit = x => x >= 48 && x <= 57;

  for (let i = 0, n = Math.min(a.length, b.length); i < n; i++) {
    let aCharCode = a.charCodeAt(i), bCharCode = b.charCodeAt(i);
    
    if (aCharCode !== bCharCode) {
      if (isDigit(aCharCode) && !isDigit(bCharCode)) return 1;
      if (isDigit(bCharCode) && !isDigit(aCharCode)) return -1;
      return aCharCode - bCharCode;
    }
  }

  return a.length - b.length;
});

console.log(objects)

For the given input, this prints out

[
  {
    "name": "A"
  },
  {
    "name": "AA"
  },
  {
    "name": "A1"
  },
  {
    "name": "B"
  },
  {
    "name": "1"
  },
  {
    "name": "2"
  }
]

Solution with two _.sortBy()

One for priotizing alphabets first, then another one for sorting the elements.

In my opinion it's more readable and it will have no performance impact.

const objects = [
  {name: 'B'},
  {name: '2'},
  {name: '1'},
  {name: 'A'}
]

const result = _.sortBy(_.sortBy(objects, o => !isNaN(parseInt(o.name)), 'name'))

console.log(result)

<script src="https://lodash./vendor/cdn.jsdelivr/lodash/4.17.3/lodash.min.js"></script>

Partition the input, sort separately and join back:

Code:

const _ = require('lodash');

const customSort = (a) => _.chain(_.partition(a, i => isNaN(i.name))).flatMap(p => _.sortBy(p, 'name')).value();

const input = [
    { name: '1' },
    { name: 'A' },
    { name: '6' },
    { name: 'B' },
    { name: 'a' },
    { name: '0' },
    { name: '3' }];

console.log(customSort(input));

Output:

[ { name: 'A' },
  { name: 'B' },
  { name: 'a' },
  { name: '0' },
  { name: '1' },
  { name: '3' },
  { name: '6' } ]

If name is an integer prefix it with z for parison.

var objects = [
  {name: 'z'},
  {name: 'A'},
  {name: '1'},
  {name: 'B'}
], sorted = _.sortBy( objects, [
        function(d) {
            return !isNaN(parseFloat(d.name))
                   && isFinite(d.name)
                       ? 'z' + d.name
                       : d.name;
        }
    ]
);
console.log(sorted);

<script src="https://lodash./vendor/cdn.jsdelivr/lodash/4.17.3/lodash.min.js"></script>

本文标签： javascriptLodash Sort array of objects prioritizing alphabets first followed by numbersStack Overflow