Order object keys by two conditions but give priority to the first one

May 31, 2022

I am trying to sort the keys of an object accoring to two conditons, first by having the word Current and then by Conv but I dont wont the last condition to undo the previous one.

const obj = {
  'Additional Traffic': 2,
  'Current Conv': 1,
  'Additional Conv': 0.5,
  'Current Rev': 100,
  'Additional Rev': 50
}

const res = Object.keys(obj).sort((a, b) => a.includes('Current') &&  a.includes('Conv') ? -1 : 0)

// Expected output
// Current Conv  
// Current Rev 
// Additional Traffic  
// Additional Conv 
// Additional Rev  

console.log(res)

>Solution :

usually you would have a function which compare using first criteria and if result is 0 (equality) you compare with next criteria.

So for you that would be:

const obj = {
  'Additional Traffic': 2,
  'Current Conv': 1,
  'Additional Conv': 0.5,
  'Current Rev': 100,
  'Additional Rev': 50
}

const res = Object.keys(obj).sort((a, b) => {
  let result = b.indexOf('Current') - a.indexOf('Current');
  if (result === 0) {
    result = b.indexOf('Conv') - a.indexOf('Conv');
  }
  return result;
});

// Expected output
// Current Conv  
// Current Rev 
// Additional Traffic  <-- need one more rule for this one to be sorted properly
// Additional Conv 
// Additional Rev  

console.log(res)

Note that if you have a lot of words to check you can use an array like so:

const obj = {
  'Additional Traffic': 2,
  'Current Conv': 1,
  'Additional Conv': 0.5,
  'Current Rev': 100,
  'Additional Rev': 50
}

const SORT_ARRAY = ['Current', 'Traffic', 'Conv'];

const res = Object.keys(obj).sort((a, b) => {
  let sortCriteriaIdx = 0;
  let result = 0;
  while (result === 0 && sortCriteriaIdx < SORT_ARRAY.length) {
    const criteria = SORT_ARRAY[sortCriteriaIdx];
    result = b.indexOf(criteria) - a.indexOf(criteria);
    sortCriteriaIdx++;
  }
  return result;
});

// Expected output
// Current Conv  
// Current Rev 
// Additional Traffic
// Additional Conv 
// Additional Rev  

console.log(res)