Sort array of object javascript by attribute

Question

I have an unsorted array of object having 2 revelant property: type, and date. I need to sort this array:

By date and
By type (for every year, deposit should go first before withdrawal)

Here is an example of input:

let i = [
    {
        date:'2017',
        type:'withdrawal',
        amount:-5
    },
    {
        date:'2016',
        type:'deposit',
        amount:12
    },
    {
        date:'2018',
        type:'deposit',
        amount:54
    },
    {
        date:'2017',
        type:'deposit',
        amount:20
    },
    {
        date:'2016',
        type:'withdrawal',
        amount:55
    },
    {
        date:'2018',
        type:'withdrawal',
        amount:54
    }
]

The goal is to output something like this:

let o = [
    {
        date:'2016',
        type:'deposit',
        amount:12
    },
    {
        date:'2016',
        type:'withdrawal',
        amount:55
    },
    {
        date:'2017',
        type:'deposit',
        amount:20
    },
    {
        date:'2017',
        type:'withdrawal',
        amount:-5
    },
    {
        date:'2018',
        type:'deposit',
        amount:54
    },
    {
        date:'2018',
        type:'withdrawal',
        amount:54
    }
]

So far I managed to sort the array by date using:

o = i.sort((a,b)=>(a.date - b.date))

But I can't find a way to sort it by type

Nitish Narang · Accepted Answer · 2018-11-17 06:50:50Z

3

You can use "sort" like below. By using "localeCompare" it will sort "type" in increasing order - which is "deposit" will come before "withdrawl" as "d" comes before "w"

That is use this -

i.sort((a,b) => ((+a.date) - (+b.date) || (a.type.localeCompare(b.type))))

you sort first by "date" and if dates are same then it goes in OR condition (as a.date - b.date will be 0) to check "type"

let i = [
    {
        date:'2017',
        type:'withdrawal',
        amount:-5
    },
    {
        date:'2016',
        type:'deposit',
        amount:12
    },
    {
        date:'2018',
        type:'deposit',
        amount:54
    },
    {
        date:'2017',
        type:'deposit',
        amount:20
    },
    {
        date:'2016',
        type:'withdrawal',
        amount:55
    },
    {
        date:'2018',
        type:'withdrawal',
        amount:54
    }
]  

i.sort((a,b) => ((+a.date) - (+b.date) || (a.type.localeCompare(b.type))))

console.log(i)

edited Nov 17, 2018 at 6:50

answered Nov 17, 2018 at 6:39

Nitish Narang

4,2042 gold badges17 silver badges22 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

TSR Over a year ago

Could you please explain

Nitish Narang Over a year ago

@TSR I have added "sort" explanation.. Pls let me know if anything is unclear. Thanks.

Hassan Imam · Accepted Answer · 2018-11-17 06:58:09Z

0

You can use string#localCompare to sort the array first based on date and then on type.

let arr = [ { date:'2017', type:'withdrawal', amount:-5 }, { date:'2016', type:'deposit', amount:12 }, { date:'2018', type:'deposit', amount:54 }, { date:'2017', type:'deposit', amount:20 }, { date:'2016', type:'withdrawal', amount:55 }, { date:'2018',type:'withdrawal', amount:54 } ];
arr.sort((a,b) => a.date.localeCompare(b.date) || a.type.localeCompare(b.type));
console.log(arr);

answered Nov 17, 2018 at 6:58

Hassan Imam

22.6k6 gold badges45 silver badges53 bronze badges

Comments

Gabor Szekely · Accepted Answer · 2018-11-17 07:21:15Z

0

While probably not the most optimal solution, I concat'ed the type onto the date as a string for both "a" and "b" in the Array.prototype.sort method, and sorted the array based on that.

i.sort((a,b) => {
  let aStr = `${a.date}${a.type}`;
  let bStr = `${b.date}${b.type}`;
  if(aStr > bStr) {
    return 1;
  } else if(aStr === bStr) {
    return 0;
  } else {
    return -1;
  }
});

Hope that helps!

edited Nov 17, 2018 at 7:21

answered Nov 17, 2018 at 7:13

Gabor Szekely

1,2588 silver badges15 bronze badges

Collectives™ on Stack Overflow

Sort array of object javascript by attribute

3 Answers 3

2 Comments

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

3 Answers 3

2 Comments

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related