Reference
C Library
IOstream Library
Strings library
STL Containers
STL Algorithms
Miscellaneous
IOstream Library
manipulators
classes:
filebuf
fstream
ifstream
ios
iostream
ios_base
istream
istringstream
ofstream
ostream
ostringstream
streambuf
stringbuf
stringstream
objects:
cerr
cin
clog
cout
types:
fpos
streamoff
streampos
streamsize
ios_base
ios_base::ios_base
ios_base::~ios_base
member classes:
ios_base::failure
ios_base::Init
member functions:
ios_base::flags
ios_base::getloc
ios_base::imbue
ios_base::iword
ios_base::precision
ios_base::pword
ios_base::register_callback
ios_base::setf
ios_base::sync_with_stdio
ios_base::unsetf
ios_base::width
ios_base::xalloc
member types:
ios_base::event
ios_base::event_callback
ios_base::fmtflags
ios_base::iostate
ios_base::openmode
ios_base::seekdir


ios_base::width

public member function
streamsize width ( ) const;
streamsize width ( streamsize wide );

Get/set field width

The first syntax returns the current value of the field width.
The second syntax sets a new field width for the object.

The field width determines the minimum number of characters to be written in some output representations. If the standard width of the representation is shorter than the field width, the representation is padded with fill characters at a point determined by the format flag adjustfield (left, right or internal).

The fill character can be retrieved or changed by calling the member function ios::fill.

The format flag adjustfield can be modified by calling the member functions flags or setf, by inserting one of the following manipulators: left, right and internal, or by inserting the parameterized manipulator setiosflags.

The field width can also be modified using the parameterized manipulator setw.

Parameters

wide
New value for the stream's field width. This is an integral value of type streamsize.

Return Value

The value of the field width before the call.

Example

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// field width
#include <iostream>
using namespace std;
int main () {
  cout << 100 << endl;
  cout.width(10);
  cout << 100 << endl;
  cout.fill('x');
  cout.width(15);
  cout << left << 100 << endl;
  return 0;
}


Output:

100
       100
100xxxxxxxxxxxx

See also

setw Set field width (manipulator function)
ios_base::flags Get/set format flags (public member function)
ios_base::setf Set specific format flags (public member function)
ios::fill Get/set the fill character (public member function)