c++ std::string to boolean

Question

I am currently reading from an ini file with a key/value pair. i.e.

isValid = true 

When get the key/value pair I need to convert a string of 'true' to a bool. Without using boost what would be the best way to do this?

I know I can so a string compare on the value ("true", "false") but I would like to do the conversion without having the string in the ini file be case sensitive.

Thanks

Answer 1

Another solution would be to use tolower() to get a lower-case version of the string and then compare or use string-streams:

#include <sstream> #include <string> #include <iomanip> #include <algorithm> #include <cctype>  bool to_bool(std::string str) {     std::transform(str.begin(), str.end(), str.begin(), ::tolower);     std::istringstream is(str);     bool b;     is >> std::boolalpha >> b;     return b; }  // ... bool b = to_bool("tRuE");