ios_base::fmtflags

Constants to specify the appearance of output.

static const fmtflags boolalpha, dec, fixed, hex,
   internal, left, oct, right, scientific,
   showbase, showpoint, showpos, skipws, unitbuf,
   uppercase, adjustfield, basefield, floatfield;

Remarks

Supports the manipulators in ios.

The type is a bitmask type that describes an object that can store format flags. The distinct flag values (elements) are:

  • dec, to insert or extract integer values in decimal format.

  • hex, to insert or extract integer values in hexadecimal format.

  • oct, to insert or extract integer values in octal format.

  • showbase, to insert a prefix that reveals the base of a generated integer field.

  • internal, to pad to a field width as needed by inserting fill characters at a point internal to a generated numeric field. (For information on setting the field width, see setw).

  • left, to pad to a field width as needed by inserting fill characters at the end of a generated field (left justification).

  • right, to pad to a field width as needed by inserting fill characters at the beginning of a generated field (right justification).

  • boolalpha, to insert or extract objects of type bool as names (such as true and false) rather than as numeric values.

  • fixed, to insert floating-point values in fixed-point format (with no exponent field).

  • scientific, to insert floating-point values in scientific format (with an exponent field).

  • showpoint, to insert a decimal point unconditionally in a generated floating-point field.

  • showpos, to insert a plus sign in a nonnegative generated numeric field.

  • skipws, to skip leading white space before certain extractions.

  • unitbuf, to flush output after each insertion.

  • uppercase, to insert uppercase equivalents of lowercase letters in certain insertions.

In addition, several useful values are:

  • adjustfield, a bitmask defined as internal | left | right

  • basefield, defined as dec | hex | oct

  • floatfield, defined as fixed | scientific

For examples of functions that modify these format flags, see <ios> Members (under Manipulators) and <iomanip> Members.

Requirements

Header: <ios>

Namespace: std

See Also

Concepts

ios_base Class

ios_base Members

iostream Programming

iostreams Conventions