How to sort an array using regex in Javascript?

Question

I have an array which looks like this

arr = ["#0abc", "#2egf", "#0pol kol", "#1loa", "#2ko pol"]

As you can see, each element in the array has #n associated with it where n is any number between 0-9. Now based on the n, I want to sort by array in ascending order such that the final output looks like this

[ '#0abc', '#0pol kol', '#1loa', '#2egf', '#2ko pol' ]

So this is what I do

rankWordMap = {}
finalArr = []
arr.forEach(function(entry) {
    rank = entry.charAt(1)
    if(rankWordMap[rank]) {
        rankWordMap[rank].push(entry);
    }
    else {
        rankWordMap[rank] = [entry];
    }

})

for (var key in rankWordMap) {
    if (rankWordMap.hasOwnProperty(key)) {
        finalArr.push(...rankWordMap[key])
    }
}

console.log(finalArr)

I get the expected output but as you can see, it's pretty inefficient. Besides I could have hundreds of elements sometimes where I would like to quickly sort it rather than doing it this way.

Is there any shorter way to implement this? I am specifically looking for a regex solution but other solutions are fine too.

`arr.sort( (a,b) => a.match(/#(\d+)/)[1] - b.match(/#(\d+)/)[1] )` — Wiktor Stribiżew, May 11 '20 at 09:07

score 1 · Accepted Answer · answered May 11 '20 at 09:05

1

No need for regex, just sort based on the integer value of the second character in each entry:

arr = ["#0abc", "#2egf", "#0pol kol", "#1loa", "#2ko pol"];

arr.sort((a, b) => parseInt(a[1]) - parseInt(b[1]));
console.log(arr);

answered May 11 '20 at 09:05

Nick

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wow this is nice non regex solution. – Souvik Ray May 11 '20 at 09:25
@SouvikRay I'm glad it was helpful. – Nick May 11 '20 at 09:28

score 1 · Answer 2 · answered May 11 '20 at 09:05

You could match the first coming digits and take this value for sorting.

var
    getValue = string => string.match(/\d+/),
    array = ["#0abc", "#2egf", "#0pol kol", "#1loa", "#2ko pol"];

array.sort((a, b) => getValue(a) - getValue(b));

console.log(array);

How to sort an array using regex in Javascript?

2 Answers2