std::basic_istream
Defined in header
<istream>
|
||
template<
class CharT, |
||
The class template basic_istream
provides support for high level input operations on character streams. The supported operations include formatted input (e.g. integer values or whitespace-separated characters and characters strings) and unformatted input (e.g. raw characters and character arrays). This functionality is implemented in terms of the interface provided by the underlying basic_streambuf
class, accessed through the basic_ios
base class. The only non-inherited data member of basic_istream
, in most implementations, is the value returned by basic_istream::gcount().
Two specializations for common character types are defined:
Defined in header
<istream> |
|
Type | Definition |
istream
|
basic_istream<char> |
wistream
|
basic_istream<wchar_t> |
Contents |
[edit] Global objects
Two global basic_istream objects are provided by the standard library.
Defined in header
<iostream> |
|
reads from the standard C input stream stdin (global object) |
[edit] Member types
Member type | Definition |
char_type
|
CharT |
traits_type
|
Traits |
int_type
|
Traits::int_type |
pos_type
|
Traits::pos_type |
off_type
|
Traits::off_type |
[edit] Member functions
constructs the object (public member function) |
|
[virtual]
|
destructs the object (virtual public member function) |
(C++11)
|
replaces the buffer object (protected member function) |
Formatted input |
|
extracts formatted data (public member function) |
|
Unformatted input |
|
extracts characters (public member function) |
|
reads the next character without extracting it (public member function) |
|
unextracts a character (public member function) |
|
puts character into input stream (public member function) |
|
extracts characters until the given character is found (public member function) |
|
extracts and discards characters until the given character is found (public member function) |
|
extracts blocks of characters (public member function) |
|
extracts already available blocks of characters (public member function) |
|
returns number of characters extracted by last unformatted input operation (public member function) |
|
Positioning |
|
returns the input position indicator (public member function) |
|
sets the input position indicator (public member function) |
|
Miscellaneous |
|
synchronizes with the underlying storage device (public member function) |
|
(C++11)
|
swaps stream objects, except for the associated buffer (protected member function) |
[edit] Member classes
implements basic logic for preparation of the stream for input operations (public member class) |
[edit] Non-member functions
extracts characters and character arrays (function template) |
Inherited from std::basic_ios
Member types
Member type | Definition |
char_type
|
CharT |
traits_type
|
Traits |
int_type
|
Traits::int_type |
pos_type
|
Traits::pos_type |
off_type
|
Traits::off_type |
Member functions
State functions |
|
checks if no error has occurred i.e. I/O operations are available (public member function of std::basic_ios )
|
|
checks if end-of-file has been reached (public member function of std::basic_ios )
|
|
checks if a recoverable error has occurred (public member function of std::basic_ios )
|
|
checks if a non-recoverable error has occurred (public member function of std::basic_ios )
|
|
checks if an error has occurred (synonym of fail()) (public member function of std::basic_ios )
|
|
(until C++11)(since C++11)
|
checks if no error has occurred (synonym of !fail()) (public member function of std::basic_ios )
|
returns state flags (public member function of std::basic_ios )
|
|
sets state flags (public member function of std::basic_ios )
|
|
clears error and eof flags (public member function of std::basic_ios )
|
|
Formatting |
|
copies formatting information (public member function of std::basic_ios )
|
|
manages the fill character (public member function of std::basic_ios )
|
|
Miscellaneous |
|
manages exception mask (public member function of std::basic_ios )
|
|
sets the locale (public member function of std::basic_ios )
|
|
manages associated stream buffer (public member function of std::basic_ios )
|
|
manages tied stream (public member function of std::basic_ios )
|
|
narrows characters (public member function of std::basic_ios )
|
|
widens characters (public member function of std::basic_ios )
|
Inherited from std::ios_base
Member functions
Formatting |
|
manages format flags (public member function of std::ios_base )
|
|
sets specific format flag (public member function of std::ios_base )
|
|
clears specific format flag (public member function of std::ios_base )
|
|
manages decimal precision of floating point operations (public member function of std::ios_base )
|
|
manages field width (public member function of std::ios_base )
|
|
Locales |
|
sets locale (public member function of std::ios_base )
|
|
returns current locale (public member function of std::ios_base )
|
|
Internal extensible array |
|
[static]
|
returns a program-wide unique integer that is safe to use as index to pword() and iword() (public static member function of std::ios_base )
|
resizes the private storage if necessary and access to the long element at the given index (public member function of std::ios_base )
|
|
resizes the private storage if necessary and access to the void* element at the given index (public member function of std::ios_base )
|
|
Miscellaneous |
|
registers event callback function (public member function of std::ios_base )
|
|
[static]
|
sets whether C++ and C IO libraries are interoperable (public static member function of std::ios_base )
|
Member classes |
|
stream exception (public member class of std::ios_base )
|
|
initializes standard stream objects (public member class of std::ios_base )
|
Member types and constants |
|||||||||||||||||||||||||||||||||||||||
Type | Explanation | ||||||||||||||||||||||||||||||||||||||
stream open mode type
The following constants are also defined:
(typedef) |
|||||||||||||||||||||||||||||||||||||||
formatting flags type
The following constants are also defined:
(typedef) |
|||||||||||||||||||||||||||||||||||||||
state of the stream type
The following constants are also defined:
(typedef) |
|||||||||||||||||||||||||||||||||||||||
seeking direction type
The following constants are also defined:
(typedef) |
|||||||||||||||||||||||||||||||||||||||
specifies event type (enum) |
|||||||||||||||||||||||||||||||||||||||
callback function type (typedef) |