operator>>(std::basic_istream)

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template< class CharT, class Traits > basic_istream<CharT,Traits>& operator>>( basic_istream<CharT,Traits>& st, CharT& ch ); template< class Traits > basic_istream<char,Traits>& operator>>( basic_istream<char,Traits>& st, signed char& ch ); template< class Traits > basic_istream<char,Traits>& operator>>( basic_istream<char,Traits>& st, unsigned char& ch );	(1)

template< class CharT, class Traits> basic_istream<CharT,Traits>& operator>>( basic_istream<CharT,Traits>& st, CharT* s ); template< class Traits > basic_istream<char,Traits>& operator>>( basic_istream<char,Traits>& st, signed char* s ); template< class Traits > basic_istream<char,Traits>& operator>>( basic_istream<char,Traits>& st, unsigned char* s );	(2)

template< class CharT, class Traits, class T > basic_istream<CharT,Traits>& operator>>( basic_istream<CharT,Traits>&& st, T& value );	(3)	(since C++11)

Performs character input operations.

1) Behaves as an FormattedInputFunction. After constructing and checking the sentry object, which may skip leading whitespace, extracts a character and stores it to ch.

2) Behaves as an FormattedInputFunction. After constructing and checking the sentry object, which may skip leading whitespace, extracts successive characters and stores them at successive locations of a character array whose first element is pointed to by s. The extraction stops if one of the following conditions are met:

a whitespace character (as determined by the ctype<CharT> facet) is found. The whitespace character is not extracted.
this->width() - 1 characters are extracted

In either case, an additional null character value CharT() is stored at the end of the output.

3) Calls the appropriate extraction operator, given an rvalue reference to an input stream object (equivalent to st >> value).

#include <iostream>
#include <iomanip>
#include <sstream>
 
int main()
{
    std::string input = "n greetings";
    std::istringstream stream(input);
    char c;
    const int MAX = 6;
    char cstr[MAX];
 
    stream >> c >> std::setw(MAX) >> cstr;
    std::cout << "c = " << c << '\n'
              << "cstr = " << cstr << '\n';
 
    double f;
    std::istringstream("1.23") >> f; // rvalue stream extraction
    std::cout << "f = " << f << '\n';
}

Output:

c = n
cstr = greet
f = 1.23

[edit] See also


operator>>	extracts formatted data (public member function)

Language
Concepts
Utilities library
Strings library
Containers library
Algorithms library
Iterators library
Numerics library
Input/output library
Localizations library
Regular expressions library (C++11)
Atomic operations library (C++11)
Thread support library (C++11)

st	-	input stream to extract the data from
ch	-	reference to a character to store the extracted character to
s	-	pointer to a character string to store the extracted characters to

operator>>(std::basic_istream)

Contents

[edit] Notes

[edit] Parameters

[edit] Return value

[edit] Example

[edit] See also