Question

I have function in JavaScript:

function calc(num) {
    if (num <= 22) {
            return parseInt(num);
    } else {
            num += '';
            var curr = 0;
            for (var i = 0; i < num['length']; i++) {
                    curr += parseInt(num[i]);
            };
            return curr;
    };
};

This function calculates new number like:
if I have number greater than 22, this function returns new number which is a sum of it’s subdigits (e.g. 28 > 22 => return (2+8) ).

This function works great in Firefox, but I’m getting “NaN” error in Internet Explorer with numbers greater than 22. So the problem must be in “else”.

What’s wrong?

Answer 1

You need to num.charAt(i) as you cannot access string characters with String[offset] in IE.

(s = "qwe"; alert(typeof s[1] === 'undefined') is true)