What are you putting to upper case?
Yes, I want whatever they are writing and pressing shift to be in upper case(normally the first letter).
Is like this what you mean?
} else if (theseKeys.indexOf('shift') > -1) {
textAdd.toUpperCase();
I did check your crib sheet and this is what appeared, but I think I might be missing something (I tried with and without the parenthesis):
Object.prototype.upper = "".toUpperCase;