Sort array of objects with dots, letters, numbers. I was able to sort by numbers, but mixed values are difficult. Not sure if possible to do it right

Question

I tried the typical sort function and checked if item is string. But I get a very strange output. Tried multiple different approaches.

 var arr = [{section:          


        

Answer 1

I propose a completely different approach. We're going to modify your strings until they are sortable by localeCompare

Here's how:

// "12" sorts before "2", prefixing to "12" and "02" fixes this
// (length should be bigger than your largest nr)
var makeLength5 = prefixWithZero.bind(null, 5);

// This function generates a string that is sortable by localeCompare
var toSortableString = function(obj) {
  return obj.section
    .replace(/\./g, "z")            // Places `12A` before `12.` but after `12`
    .replace(/\d+/g, makeLength5);  // Makes every number the same length
};

var arr = [{section:"12.2.a"},{section:"12.2.b.iii"},{section:"12.2.c"},{section:"12"},{section:"12A"},{section:"12.3.b"},{section:"12.3.c"},{section:"Q2"},{section:"Q32"},{section:"Q6"},{section:"Q5"}];
var arr2 = arr.sort(function(a, b) {
  return toSortableString(a).localeCompare(toSortableString(b));
});

console.log(JSON.stringify(arr2.map(function(s){ return s.section; }), null, 2));

// Helper methods
function prefixWithZero(length, str) {
  while (str.length < length) {
    str = "0" + str;
  }
  return str;
};