Now my approach is to generate only one letter, but if there is a lot of data and it comes after column Z, my code breaks.
Working code that will give a, d:
const countData = [1, 2, 3, 4].length;
const initialLetter = 'A'.toLowerCase();
const initialLetterNumber = initialLetter.charCodeAt(0) - 97;
const lastLetter = String.fromCharCode(
initialLetterNumber + countData - 1 + 97
);
console.log(initialLetter, lastLetter);
Non-working code, in this case I want to get z, ac.
const countData = [1, 2, 3, 4].length;
const initialLetter = 'Z'.toLowerCase();
const initialLetterNumber = initialLetter.charCodeAt(0) - 97;
const lastLetter = String.fromCharCode(
initialLetterNumber + countData - 1 + 97
);
console.log(initialLetter, lastLetter);
Some inputs and wanted result:
input: a, data length: 1 output: a,
input: a, data length: 2 output: b,
input: a, data length: 3 output: c,
input: a, data length: 4 output: d,
input: a, data length: 5 output: e,
input: z, data length: 1 output: z,
input: z, data length: 2 output: aa,
input: z, data length: 3 output: ab,
input: z, data length: 4 output: ac,
input: z, data length: 5 output: ad,
input: ad, data length: 1 output: ad,
input: ad, data length: 2 output: ae,
input: ad, data length: 3 output: af,
input: ad, data length: 4 output: ag,
input: ad, data length: 5 output: ah,
input: az, data length: 1 output: az,
input: az, data length: 2 output: ba,
input: az, data length: 3 output: bb,
input: az, data length: 4 output: bc,
input: az, data length: 5 output: bd,
input: bz, data length: 1 output: bz,
input: bz, data length: 2 output: ca,
input: bz, data length: 3 output: cb,
input: bz, data length: 4 output: cc,
input: bz, data length: 5 output: cd,
...
You could take two functions to get an integer value from a string and a string from an integer value.
With this functions, you could adjust the numerical value and get an encoded string of this value.
const
decode = string => [...string].reduce((r, c) => r * 26 + parseInt(c, 36) - 9, 0) - 1,
encode = integer => {
let result = '';
do {
result = (integer % 26 + 10).toString(36) + result;
integer = Math.floor(integer / 26) - 1;
} while (integer >= 0)
return result;
};
for (let i = 0; i < 26 * 27 + 1; i++) {
const s = encode(i);
document.getElementById('out').innerHTML += [i, s, decode(s)].join(' ') + '\n';
}<pre id="out"></pre>