How do you sort an array by two fields (date included)

Question

I have an array of objects that I want to sort first by date and next by its numeric value.

let arr = [  
  {date: 2018-06-19 12:05:43.232Z, value: 3},
  {date: 2018-06-20 12:05:43.232Z, value: 4},  
  {date: 2018-06-18 12:05:43.232Z, value: 2},  
  {date: 2018-06-20 12:05:43.232Z, value: 4}, 
  {date: 2018-06-19 12:05:43.232Z, value: 5},     
  {date: 2018-06-18 12:05:43.232Z, value: 5},  
  {date: 2018-06-20 12:05:43.232Z, value: 5},  
  {date: 2018-06-19 12:05:43.232Z, value: 4},  
]

I want to sort each index by the date and the value so the result would be :

let arr = [
  {date: 2018-06-18 12:05:43.232Z, value: 2},
  {date: 2018-06-18 12:05:43.232Z, value: 5},

  {date: 2018-06-19 12:05:43.232Z, value: 3},
  {date: 2018-06-19 12:05:43.232Z, value: 4},
  {date: 2018-06-19 12:05:43.232Z, value: 5}, 

  {date: 2018-06-20 12:05:43.232Z, value: 3},
  {date: 2018-06-20 12:05:43.232Z, value: 4},     
  {date: 2018-06-20 12:05:43.232Z, value: 5},     
]

How can it be done?

By googling `js array sort`. https://stackoverflow.com/questions/979256/sorting-an-array-of-javascript-objects — u_mulder, Jun 19 '18 at 12:37
not the same issue. I am looking to sort by two fields. Thats my problem. I can sort by date or by value but am looking to sort by both — obiwankenoobi, Jun 19 '18 at 12:42

baao · Accepted Answer · 2018-06-19T12:54:51.410

5

You can use Array.sort with ||

const res = arr.sort((a, b) => Date.parse(a.date) - Date.parse(b.date) || a.value - b.value);
console.log(res);

<script>
let arr = [{
    date: '2018-06-19 12:05:43.232Z',
    value: 3
  },
  {
    date: '2018-06-20 12:05:43.232Z',
    value: 4
  },
  {
    date: '2018-06-18 12:05:43.232Z',
    value: 2
  },
  {
    date: '2018-06-20 12:05:43.232Z',
    value: 4
  },
  {
    date: '2018-06-19 12:05:43.232Z',
    value: 5
  },
  {
    date: '2018-06-18 12:05:43.232Z',
    value: 5
  },
  {
    date: '2018-06-20 12:05:43.232Z',
    value: 5
  },
  {
    date: '2018-06-19 12:05:43.232Z',
    value: 4
  },
]
</script>

edited Jun 19 '18 at 12:54

answered Jun 19 '18 at 12:39

baao

71,625
17
143
203

1

thank you so much work perfectly! – obiwankenoobi Jun 19 '18 at 12:52
You're welcome @obiwankenoobi – baao Jun 19 '18 at 12:53

Boky · Answer 2 · 2018-06-19T13:01:43.567

Yo can do it using lodash library. If you check the docs of orderBy function you'll see that, it is exactly what you need.

let arr = [  
  {"date": "2018-06-19 12:05:43.232Z", "value": 3},
  {"date": "2018-06-20 12:05:43.232Z", "value": 4},  
  {"date": "2018-06-18 12:05:43.232Z", "value": 2},  
  {"date": "2018-06-20 12:05:43.232Z", "value": 4}, 
  {"date": "2018-06-19 12:05:43.232Z", "value": 5},     
  {"date": "2018-06-18 12:05:43.232Z", "value": 5},  
  {"date": "2018-06-20 12:05:43.232Z", "value": 5},  
  {"date": "2018-06-19 12:05:43.232Z", "value": 4}  
]

Applying _orderBy on your array as follows:

_.orderBy(arr, ['date', 'value'], ['asc', 'asc']);

will get you the result that you want.

Check the example below:

let arr = [  
  {"date": "2018-06-19 12:05:43.232Z", "value": 3},
  {"date": "2018-06-20 12:05:43.232Z", "value": 4},  
  {"date": "2018-06-18 12:05:43.232Z", "value": 2},  
  {"date": "2018-06-20 12:05:43.232Z", "value": 4}, 
  {"date": "2018-06-19 12:05:43.232Z", "value": 5},     
  {"date": "2018-06-18 12:05:43.232Z", "value": 5},  
  {"date": "2018-06-20 12:05:43.232Z", "value": 5},  
  {"date": "2018-06-19 12:05:43.232Z", "value": 4}  
]



console.log(_.orderBy(arr, ['date', 'value'], ['asc', 'asc']))

<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.10/lodash.js"></script>

How do you sort an array by two fields (date included)

2 Answers2