I want to output an integer to a std::stringstream with the equivalent format of printf's %02d. Is there an easier way to achieve this than:
std::stringstream stream;
stream.setfill('0');
stream.setw(2);
stream << value;
Is it possible to stream some sort of format flags to the stringstream, something like (pseudocode):
stream << flags("%02d") << value;
You can use the standard manipulators from <iomanip> but there isn't a neat one that does both fill and width at once:
stream << std::setfill('0') << std::setw(2) << value;
It wouldn't be hard to write your own object that when inserted into the stream performed both functions:
stream << myfillandw( '0', 2 ) << value;
E.g.
struct myfillandw
{
myfillandw( char f, int w )
: fill(f), width(w) {}
char fill;
int width;
};
std::ostream& operator<<( std::ostream& o, const myfillandw& a )
{
o.fill( a.fill );
o.width( a.width );
return o;
}