C++Talk.NET

thinktwice · Guest

//case 1, works fine
function(..)
{
std::ofstream out;
out.open(file);
out << "error info" <<endl;
out.close();
}

//case 2, declare it in a class
class Logger
{
public:
Logger(std::wstring file, std::ios_base::openmode mode /*undefined
too, why?*/){}
private:
std::ofstream out; //error c2079, uses undefined class
'std::basic_ofstream<_Elem, _Traits>'
}

btw, how to use ios_base:openmode? is it declared in std namespace?

thinktwice · Guest

thanks Persson , you are right,
i do include <fstream> in cpp file.
and the function implementation and the class definination is in the
header file.