Convert excel column alphabet (e.g. AA) to number (e.g., 25)

Question

In my grid the column headers are named A,B,C...,AA,AB,AC,...etc like an excel spreadsheet. How can I convert the string to number like: A => 1, B =>

Answer 1

Here's a quick example of the code you should implement. This will work with any given number of letters.

function letterToNumbers(string) {
    string = string.toUpperCase();
    var letters = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ', sum = 0, i;
    for (i = 0; i < string.length; i++) {
        sum += Math.pow(letters.length, i) * (letters.indexOf(string.substr(((i + 1) * -1), 1)) + 1);
    }
    return sum;
}