C + + iostream

Ext.: http://blog.csdn.net/ouczoe/article/details/4923413

The input and output stream is defined in <iostream> and the standard console output stream is also declared in this header file cout

Header file with control: standard header file <ios> and <iomanip>

Output stream:

Boolalpha and Noboolalpha: notifies the output stream to output bool as true and False (Boolalpha) or 1 and 0 (noboolalpha). The default is Noboolalpha.

Hex,oct,dec: 16 binary, 8 binary, 10 binary output digits respectively.

Setprecision: Sets the number of decimal places to output decimals (several after the decimal point). For example, Setprecision (5)--Take 5 digits after the decimal point.

SETW: Sets the width of the field when outputting numeric data. e.g. SETW (5).

Setfill: When the width of the number is less than the width of the set, the control can make the characters that fill the empty space. Setfill (' a ').

Showpoint and Nonshowpoint: for floating-point or double-precision numbers without fractional parts, this control forces the flow to always display decimals or not display decimals.

Endl: Encapsulates data and behavior. The number of notification flows outputs a carriage return and refreshes its buffer output.

These controls are written in front of the output parameters that need to function, such as COUT<<SETW (7) <<setfill (' & ') <<variable<<endl;

e.g. #include <iostream>

#include <iomanip>

using namespace Std;

int main (int argc, char** argv)

{

bool Testb = true;

cout<< "This is a testing of bool" <<boolalpha<<testB<<endl;

}

Input stream:

Boolalpha and Noboolalpha: the string True,false interpreted as Boolean true and False for input save (boolalpha). Noboolalpha won't explain that. The default is Noboolalpha.

Hex,oct,dec: The numbers are read in 16, 8, and 10 respectively.

Skipwa and Noskipwa: The notification flow ignores whitespace characters when doing lexical analysis or reads whitespace into tokens as a whitespace character.

WS: Traverse the control character. Ignores a string of whitespace at the current position in the stream.

C + + iostream