C++ check if string is space or null

Question

Basically I have string of whitespace \" \" or blocks of whitespace or \"\" empty in some of the lines of the files and I would

Answer 1

bool isWhitespace(std::string s){
    for(int index = 0; index < s.length(); index++){
        if(!std::isspace(s[index]))
            return false;
    }
    return true;
}