Convert numbers to letters beyond the 26 character alphabet

Question

I\'m creating some client side functions for a mappable spreadsheet export feature.

I\'m using jQuery to manage the sort order of the columns, but each column is ord

Answer 1

You can use code like this, assuming that numbers contains the numbers of your columns. So after this code you'll get the string names for your columns:

var letters = ['a', 'b', 'c', ..., 'z'];
var numbers = [1, 2, 3, ...];
var columnNames = [];
for(var i=0;i<numbers.length;i++) {
    var firstLetter = parseInt(i/letters.length) == 0 ? '' : letters[parseInt(i/letters.length)];
    var secondLetter = letters[i%letters.length-1];
    columnNames.push(firstLetter + secondLetter);
}

Answer 2

This is a very easy way:

function numberToLetters(num) {
    let letters = ''
    while (num >= 0) {
        letters = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ'[num % 26] + letters
        num = Math.floor(num / 26) - 1
    }
    return letters
}

Answer 3

I think you're looking for something like this

    function colName(n) {
        var ordA = 'a'.charCodeAt(0);
        var ordZ = 'z'.charCodeAt(0);
        var len = ordZ - ordA + 1;
      
        var s = "";
        while(n >= 0) {
            s = String.fromCharCode(n % len + ordA) + s;
            n = Math.floor(n / len) - 1;
        }
        return s;
    }

// Example:

    for(n = 0; n < 125; n++)
            document.write(n + ":" + colName(n) + "<br>");