How can I sort the following array, in a custom order, based on the prop2's last 3 letters that have to be in this order 'ABR', 'FDE', 'ZFR'

Sample input:

const arr = [
  { prop1: 3, prop2: '3FDE' },
  { prop1: 4, prop2: '5ZFR' },
  { prop1: 5, prop2: '7ABR' }
]

Expected output:

const arr = [
  { prop1: 5, prop2: '7ABR' },
  { prop1: 3, prop2: '3FDE' },
  { prop1: 4, prop2: '5ZFR' }
]

CodePudding user response：

• Using Array#sort, iterate over the array to sort it
• In every iteration, use String#substr to get the last 3 characters and String#localeCompare to compare the two strings

const arr = [ { prop1: 3, prop2: '3FDE' }, { prop1: 4, prop2: '5ZFR' }, { 
prop1: 5, prop2: '7ABR' } ];

const _getLastThree = (str = '') => str.substr(str.length - 3);
const res = arr.sort(({ prop2: a }, { prop2: b }) => 
  _getLastThree(a).localeCompare(_getLastThree(b))
);

console.log(res);

CodePudding user response：

Just use .localeCompare() in combination with .slice():

const arr=[
{prop1:5, prop2:'7ABR'},
{prop1:3, prop2:'3FDE'},
{prop1:4, prop2:'5ZFR'},
]

console.log(arr.sort((a,b)=>a.prop2.slice(-3).localeCompare(b.prop2.slice(-3))))

CodePudding user response：

You can use the Array#sort, String#substring or String#slice or String#substr and the String#localCompare methods as follows:

• substring

const arr = [ {prop1:4, prop2:'5ZFR'}, {prop1:5, prop2:'7ABR'}, {prop1:3, prop2:'3FDE'} ];

const output = arr.sort(
   (a,b) => 
   a.prop2.substring(1).localeCompare( b.prop2.substring(1) )
);

console.log( output );

With slice or substr you can use a negative n to indicate the last n characters:

const arr = [ {prop1:4, prop2:'5ZFR'}, {prop1:5, prop2:'7ABR'}, {prop1:3, prop2:'3FDE'} ];

const output = arr.sort(
   (a,b) => 
   a.prop2.slice(-3).localeCompare( b.prop2.slice(-3) )
);

console.log( output );