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

You don't have a nullstring "in some of the lines of the files".

But you can have an empty string, i.e. an empty line.

You can use e.g. std::string.length, or if you like C better, strlen function.

In order to check for whitespace, the isspace function is handy, but note that for char characters the argument should be casted to unsigned char, e.g., off the cuff,

bool isSpace( char c )
{
    typedef unsigned char UChar;
    return bool( ::isspace( UChar( c ) ) );
}

Cheers & hth.,