Sort an array except one item using TypeScript

Question

I have the following TypeScript code:

export const cgGroups = [
  {
    id: 2,
    name: 'North America & Caribbean'
  },
  {
    id: 3,
    name: 'Latin America'
  },
  {
    id: 6,
    name: 'Europe'
  },
  {
    id: 4,
    name: 'Asia Pacific'
  },
  {
    id: 1,
    name: 'Middle East & Africa'
  },
  {
    id: 7,
    name: 'International'
  }
];

I want to sort the above alphabetical except one object

{
   id: 7,
   name: 'International'
}

which I want to move it to the last of the sorted array.

I tried the below code to sort:

cgGroups = cgGroups.map(({id, name}) => ({id, name})).sort((a, b) => {
        if (a.name.toLowerCase() > b.name.toLowerCase()) {
          return 1;
        }
        if (a.name.toLowerCase() < b.name.toLowerCase()) {
          return -1;
        }
        return 0;
      });

Here is the expected output:

Asia Pacific, Europe, Latin America, Middle East & Africa, North America & Caribbean, and International

Can anyone guide me here to fix this issue?

If a.name === "International" return -1 and other if statements can follow this one. But your expected output doesn't make sense, Asia should come first (sorted alphabeticaly by name) — HMR
– HMR, Commented May 23, 2018 at 14:36
You said you want to sort alphabetically, shouldn't Asia Pacific be the first entry? — bugs
– bugs, Commented May 23, 2018 at 14:38
Sorry I have corrected it now. Thanks a lot for pointing it out :) — santosh kumar patro
– santosh kumar patro, Commented May 23, 2018 at 14:57
It doesn't work because you didn't encode the condition about the item with id: 7 into the comparison function. — axiac
– axiac, Commented May 23, 2018 at 15:44
There is no TypeScript involved in this question. It is pure JavaScript, the code you posted works in the browser. — axiac
– axiac, Commented May 23, 2018 at 16:02

axiac · Accepted Answer · 2018-05-23 15:59:40Z

2

It doesn't work because you didn't encode the condition about the item with name: 'International' into the comparison function.

It could be like this:

cgGroups = cgGroups.map(({id, name}) => ({id, name})).sort((a, b) => {
    if (a.name.toLowerCase() == 'international') {
        return +1;      // "a" is the greatest element of the array
    } else if (b.name.toLowerCase() == 'international') {
        return -1;      // "a" stays before "b" because "b" is the last item
    } else if (a.name.toLowerCase() > b.name.toLowerCase()) {
        return 1;       // regular items, compare their names
    } else if (a.name.toLowerCase() < b.name.toLowerCase()) {
        return -1;
    }

    return 0;
});

answered May 23, 2018 at 15:59

axiac

73.4k11 gold badges120 silver badges150 bronze badges

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

Comments

bugs · Accepted Answer · 2018-05-23 15:33:18Z

1

If you don't mind adding a method to the Array prototype, these are two potential solutions (the first one modifies the original array, while the second one returns a new array).

let cgGroups = [
    {
        id: 2,
        name: 'North America & Caribbean'
    },
    {
        id: 3,
        name: 'Latin America'
    },
    {
        id: 6,
        name: 'Europe'
    },
    {
        id: 4,
        name: 'Asia Pacific'
    },
    {
        id: 1,
        name: 'Middle East & Africa'
    },
    {
        id: 7,
        name: 'International'
    }
];

const sortAlph = (a, b) => {
    if (a.name.toLowerCase() > b.name.toLowerCase()) {
        return 1;
    }
    if (a.name.toLowerCase() < b.name.toLowerCase()) {
        return -1;
    }
    return 0;
}

Array.prototype.move = function (fromIndex, toIndex) {
  let element = this[fromIndex];
  this.splice(fromIndex, 1);
  this.splice(toIndex, 0, element);
}

Array.prototype.moveToTheEnd = function(index) {
  let element = this[index];
  return this.filter(x => x !== element).concat(element);
}

cgGroups
    .sort(sortAlph)
    .move(cgGroups.findIndex(x => x.name === 'International'), cgGroups.length)

newArr = cgGroups
  .sort(sortAlph)
  .moveToTheEnd(cgGroups.findIndex(x => x.name === 'International'))

console.log(cgGroups);
console.log(newArr);

edited May 23, 2018 at 15:33

answered May 23, 2018 at 15:17

bugs

15.4k6 gold badges53 silver badges55 bronze badges

1 Comment

santosh kumar patro Over a year ago

Thanks a lot for the solution. This helped me to fix the issue :)

Collectives™ on Stack Overflow

Sort an array except one item using TypeScript

2 Answers 2

Comments

1 Comment

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

Comments

1 Comment

Your Answer

Sign up or log in

Post as a guest

Linked

Related