std::setfill

C++

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showpointnoshowpoint setprecision	fixedscientifichexfloatdefaultfloat (C++11)(C++11)
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boolalphanoboolalpha
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setfill setw	internalleftright
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Defined in header <iomanip>
template< class CharT > /*unspecified*/ setfill( CharT c );

When used in an expression out << setfill(c) sets the fill character of the stream out to c.

Parameters

c

-

new value for the fill character

Return value

Returns an object of unspecified type such that if out is the name of an output stream of type std::basic_ostream<CharT, Traits>, then the expression out << setfill(n) behaves as if the following code was executed:

out.fill(n);

Notes

The current fill character may be obtained with std::ostream::fill

Example

Run this code

#include <iostream>
#include <iomanip>
int main()
{
    std::cout << "default fill: " << std::setw(10) << 42 << '\n'
              << "setfill('*'): " << std::setfill('*')
                                  << std::setw(10) << 42 << '\n';
}

Output:

default fill:         42
setfill('*'): ********42

See also

fill	manages the fill character (public member function of std::basic_ios)
internalleftright	sets the placement of fill characters (function)
setw	changes the width of the next input/output field (function)