std::ios_base::fmtflags (3) - Linux Manuals

std::ios_base::fmtflags: std::ios_base::fmtflags

NAME

std::ios_base::fmtflags - std::ios_base::fmtflags

Synopsis

typedef /*implementation defined*/ fmtflags;
static constexpr fmtflags dec = /*implementation defined*/
static constexpr fmtflags oct = /*implementation defined*/
static constexpr fmtflags hex = /*implementation defined*/
static constexpr fmtflags basefield = dec | oct | hex;
static constexpr fmtflags left = /*implementation defined*/
static constexpr fmtflags right = /*implementation defined*/
static constexpr fmtflags internal = /*implementation defined*/
static constexpr fmtflags adjustfield = left | right | internal;
static constexpr fmtflags scientific = /*implementation defined*/
static constexpr fmtflags fixed = /*implementation defined*/
static constexpr fmtflags floatfield = scientific | fixed;
static constexpr fmtflags boolalpha = /*implementation defined*/
static constexpr fmtflags showbase = /*implementation defined*/
static constexpr fmtflags showpoint = /*implementation defined*/
static constexpr fmtflags showpos = /*implementation defined*/
static constexpr fmtflags skipws = /*implementation defined*/
static constexpr fmtflags unitbuf = /*implementation defined*/
static constexpr fmtflags uppercase = /*implementation defined*/

Specifies available formatting flags. It is a BitmaskType. The following constants are defined:

Constant Explanation
dec use decimal base for integer I/O: see std::dec
oct use octal base for integer I/O: see std::oct
hex use hexadecimal base for integer I/O: see std::hex
basefield dec|oct|hex. Useful for masking operations
left left adjustment (adds fill characters to the right): see std::left
right right adjustment (adds fill characters to the left): see std::right
internal internal adjustment (adds fill characters to the internal designated point): see std::internal
adjustfield left|right|internal. Useful for masking operations
scientific generate floating point types using scientific notation, or hex notation if combined with fixed: see std::scientific
fixed generate floating point types using fixed notation, or hex notation if combined with scientific: see std::fixed
floatfield scientific|fixed. Useful for masking operations
boolalpha insert and extract bool type in alphanumeric format: see std::boolalpha
showbase generate a prefix indicating the numeric base for integer output, require the currency indicator in monetary I/O: see std::showbase
showpoint generate a decimal-point character unconditionally for floating-point number output: see std::showpoint
showpos generate a + character for non-negative numeric output: see std::showpos
skipws skip leading whitespace before certain input operations: see std::skipws
unitbuf flush the output after each output operation: see std::unitbuf
uppercase replace certain lowercase letters with their uppercase
            equivalents in certain output operations: see std::uppercase

Example

The following example shows several different ways to print the same result.
// Run this code

  #include <iostream>

  int main()
  {
      int num = 150;

      // using fmtflags as class member constants:
      std::cout.setf(std::ios_base::hex, std::ios_base::basefield);
      std::cout.setf(std::ios_base::showbase);
      std::cout << num << '\n';

      // using fmtflags as inherited class member constants:
      std::cout.setf (std::ios::hex , std::ios::basefield);
      std::cout.setf (std::ios::showbase);
      std::cout << num << '\n';

      // using fmtflags as object member constants:
      std::cout.setf(std::cout.hex, std::cout.basefield);
      std::cout.setf(std::cout.showbase);
      std::cout << num << '\n';

      // using fmtflags as a type:
      std::ios_base::fmtflags ff;
      ff = std::cout.flags();
      ff &= ~std::cout.basefield; // unset basefield bits
      ff |= std::cout.hex; // set hex
      ff |= std::cout.showbase; // set showbase
      std::cout.flags(ff);
      std::cout << num << '\n';

      // not using fmtflags, but using manipulators:
      std::cout << std::hex << std::showbase << num << '\n';
  }

Output:

  0x96
  0x96
  0x96
  0x96
  0x96