Defined in header <ios> | ||
|---|---|---|
std::ios_base& left( std::ios_base& str ); | (1) | |
std::ios_base& right( std::ios_base& str ); | (2) | |
std::ios_base& internal( std::ios_base& str ); | (3) |
Modifies the positioning of the fill characters in an output stream. left and right apply to any type being output, internal applies to integer, floating-point, and monetary output. Has no effect on input.
1) sets the adjustfield of the stream str to left as if by calling str.setf(std::ios_base::left, std::ios_base::adjustfield).
2) sets the adjustfield of the stream str to right as if by calling str.setf(std::ios_base::right, std::ios_base::adjustfield).
3) sets the adjustfield of the stream str to internal as if by calling str.setf(std::ios_base::internal, std::ios_base::adjustfield).
The initial default for standard streams is equivalent to right.
This is an I/O manipulator. It may be called with an expression such as out << std::left for any out of type std::basic_ostream or with an expression such as in >> std::left for any in of type std::basic_istream.
| str | - | reference to I/O stream |
str (reference to the stream after manipulation).
#include <iostream>
#include <iomanip>
#include <locale>
int main()
{
std::cout.imbue(std::locale("en_US.utf8"));
std::cout << "Default positioning:\n" << std::setfill('*')
<< std::setw(12) << -1.23 << '\n'
<< std::setw(12) << std::hex << std::showbase << 42 << '\n'
<< std::setw(12) << std::put_money(123, true) << "\n\n";
std::cout << "Left positioning:\n" << std::left
<< std::setw(12) << -1.23 << '\n'
<< std::setw(12) << 42 << '\n'
<< std::setw(12) << std::put_money(123, true) << "\n\n";
std::cout << "Internal positioning:\n" << std::internal
<< std::setw(12) << -1.23 << '\n'
<< std::setw(12) << 42 << '\n'
<< std::setw(12) << std::put_money(123, true) << "\n\n";
std::cout << "Right positioning:\n" << std::right
<< std::setw(12) << -1.23 << '\n'
<< std::setw(12) << 42 << '\n'
<< std::setw(12) << std::put_money(123, true) << '\n';
}Output:
Default positioning: *******-1.23 ********0x2a ***USD *1.23 Left positioning: -1.23******* 0x2a******** USD *1.23*** Internal positioning: -*******1.23 0x********2a USD ****1.23 Right positioning: *******-1.23 ********0x2a ***USD *1.23
| changes the width of the next input/output field (function) |
|
| changes the fill character (function template) |
|
| controls whether prefix is used to indicate numeric base (function) |
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