8.4.1: Formatting Output Continued
- Page ID
- 29079
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Formatting using Manipulators
The second way you can alter the format parameters of a stream is through the use of special functions called manipulators that can be included in an I/O expression.
The standard manipulators are shown below:
- boolalpha: The boolalpha manipulator of stream manipulators in C++ is used to turn on bool alpha flag
- dec: The dec manipulator of stream manipulators in C++ is used to turn on the dec flag
- endl: The endl manipulator of stream manipulators in C++ is used to Output a newline character.
- and: The and manipulator of stream manipulators in C++ is used to Flush the stream
- ends: The ends manipulator of stream manipulators in C++ is used to Output a null
- fixed: The fixed manipulator of stream manipulators in C++ is used to Turns on the fixed flag
- flush: The flush manipulator of stream manipulators in C++ is used to Flush a stream
- hex: The hex manipulator of stream manipulators in C++ is used to Turns on hex flag
- internal: The internal manipulator of stream manipulators in C++ is used to Turns on internal flag
- left: The left manipulator of stream manipulators in C++ is used to Turns on the left flag
- noboolalpha: The noboolalpha manipulator of stream manipulators in C++ is used to Turns off bool alpha flag
- noshowbase: The noshowbase manipulator of stream manipulators in C++ is used to Turns off showcase flag
- noshowpoint: The noshowpoint manipulator of stream manipulators in C++ is used to Turns off show point flag
- noshowpos: The noshowpos manipulator of stream manipulators in C++ is used to Turns off showpos flag
- noskipws: The noskipws manipulator of stream manipulators in C++ is used to Turns off skipws flag
- nounitbuf: The nounitbuf manipulator of stream manipulators in C++ is used to Turns off the unit buff flag
- nouppercase: The nouppercase manipulator of stream manipulators in C++ is used to Turns off the uppercase flag
- oct: The oct manipulator of stream manipulators in C++ is used to Turns on oct flag
- resetiosflags(fmtflags f): The resetiosflags manipulator of stream manipulators in C++ is used to Turns off the flag specified in f
- right: The right manipulator of stream manipulators in C++ is used to Turns on the right flag
- scientific: The scientific manipulator of stream manipulators in C++ is used to Turns on scientific flag
- setbase(int base): The setbase manipulator of stream manipulators in C++ is used to Set the number base to base
- setfill(int ch): The setfill manipulator of stream manipulators in C++ is used to Set the fill character to ch
- setiosflags(fmtflags f): The setiosflags manipulator of stream manipulators in C++ is used to Turns on the flag specified in f
- setprecision(int p): The setprecision manipulator of stream manipulators in C++ is used to Set the number of digits of precision
- setw(int w): The setw manipulator of stream manipulators in C++ is used to Set the field width to w
- showbase: The showbase manipulator of stream manipulators in C++ is used to Turns on showbase flag
- showpoint: The showpoint manipulator of stream manipulators in C++ is used to Turns on show point flag
- showpos: The showpos manipulator of stream manipulators in C++ is used to Turns on showpos flag
- skipws: The skipws manipulator of stream manipulators in C++ is used to Turns on skipws flag
- unitbuf: The unitbuf manipulator of stream manipulators in C++ is used to turn on unitbuf flag
- uppercase: The uppercase manipulator of stream manipulators in C++ is used to turn on the uppercase flag
- ws: The ws manipulator of stream manipulators in C++ is used to skip leading white space
To access manipulators that take parameters (such as setw( )), you must include “iomanip” header file in your program.
#include <iomanip> #include <iostream> using namespace std; int main() { // performs same as setf( ) - adds the = sign to the output cout << setiosflags(ios::showpos); cout << 123 << endl; // This takes the value 100 and turns it into a hex value (which is 64) cout << hex << 100 << endl; // Set the field width to 10 using setw() cout << setfill('*') << setw(10) << 2343.0 << endl; return 0; }
Adapted from:
"Formatted I/O in C++" by Somil Singh, Geeks for Geeks is licensed under CC BY-SA 4.0