std::basic_istream::operator>>
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                    < cpp | io | basic istream
                    
                                                            
                    | basic_istream& operator>>( short& value ); basic_istream& operator>>( unsigned short& value ); | (1) | |
| basic_istream& operator>>( int& value ); basic_istream& operator>>( unsigned int& value ); | (2) | |
| basic_istream& operator>>( long& value ); basic_istream& operator>>( unsigned long& value ); | (3) | |
| basic_istream& operator>>( long long& value ); basic_istream& operator>>( unsigned long long& value ); | (4) | (since C++11) | 
| basic_istream& operator>>( float& value ); basic_istream& operator>>( double& value ); | (5) | |
| basic_istream& operator>>( bool& value ); | (6) | |
| basic_istream& operator>>( void*& value ); | (7) | |
| basic_istream& operator>>( std::ios_base& (*func)(std::ios_base&) ); | (8) | |
| basic_istream& operator>>( std::basic_ios<CharT,Traits>& (*func)(std::basic_ios<CharT,Traits>&) ); | (9) | |
| basic_istream& operator>>( basic_istream& (*func)(basic_istream&) ); | (10) | |
| basic_istream& operator>>( std::basic_streambuf<CharT,Traits>* sb ); | (11) | |
1-4) Behaves as a 
FormattedInputFunction. After constructing and checking the sentry object, which may skip leading whitespace, extracts an integer value by calling std::num_get::get()5) Behaves as a 
FormattedInputFunction. After constructing and checking the sentry object, which may skip leading whitespace, extracts a floating point value by calling std::num_get::get()6) Behaves as a 
FormattedInputFunction. After constructing and checking the sentry object, which may skip leading whitespace, extracts bool value by calling std::num_get::get()7) Behaves as a 
FormattedInputFunction. After constructing and checking the sentry object, which may skip leading whitespace, extracts a generic pointer value by calling std::num_get::get()8-10) Calls func(*this);, where 
func is an I/O manipulator.11) Behaves as an 
 UnformattedInputFunction. After constructing and checking the sentry object, extracts all data from the input stream and stores it to sb. The extraction stops if one of the following conditions are met:
- end-of-file occurs on the input sequence;
- inserting in the output sequence fails (in which case the character to be inserted is not extracted);
-  an exception occurs (in which case the exception is caught, and only rethrown if failbitis enabled inexceptions()).
 
sb is a null pointer of it no characters were inserted into sb, calls setstate(failbit) (which may throw std::ios_base::failure if enabled).| If extraction fails (e.g. if a letter was entered where a digit is expected), valueis left unmodified andfailbitis set. | (until C++11) | 
| If extraction fails, zero is written to valueandfailbitis set. If extraction results in the value too large or too small to fit invalue, std::numeric_limits<T>::max() or std::numeric_limits<T>::min() is written andfailbitflag is set. | (since C++11) | 
| Contents | 
[edit] Parameters
| value | - | reference to an integer or floating-point value to store the extracted value to | 
| func | - | pointer to I/O manipulator function | 
| sb | - | pointer to the streambuffer to write all the data to | 
[edit] Return value
1-9,11) *this
10) func(*this)
[edit] Example
Run this code
#include <iostream> #include <iomanip> #include <sstream> int main() { std::string input = "41 3.14 false hello world"; std::istringstream stream(input); int n; double f; bool b; stream >> n >> f >> std::boolalpha >> b; std::cout << "n = " << n << '\n' << "f = " << f << '\n' << "b = " << std::boolalpha << b << '\n'; // extract the rest using the streambuf overload stream >> std::cout.rdbuf(); std::cout << '\n'; }
Output:
n = 41 f = 3.14 b = false hello world
[edit] See also
| extracts characters and character arrays (function template) | |
| performs stream input and output on strings (function template) | |
| performs stream input and output of bitsets (function template) | |
| serializes and deserializes a complex number (function template) | |
| performs stream input and output on pseudo-random number engine (function template) | |
| performs stream input and output on pseudo-random number distribution (function template) | |
| extracts blocks of characters (public member function) | |
| extracts already available blocks of characters (public member function) | |
| extracts characters (public member function) | |
| extracts characters until the given character is found (public member function) | 


