std::wstring_convert

C++

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Named requirements

Language support library

Concepts library (C++20)

Diagnostics library

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)

Filesystem library (C++17)

Technical Specifications

Localizations library

Locales and facets
locale
use_facet	has_facet
Character classification
isspace isblank (C++11) iscntrl isupper islower isalpha	isdigit ispunct isxdigit isalnum isprint isgraph
Conversions
toupper tolower	wstring_convert (C++11) wbuffer_convert (C++11)
Facet category base classes
ctype_base codecvt_base messages_base	time_base money_base
Facet categories
ctype ctype<char> codecvt collate messages time_get time_put	num_get num_put numpunct money_get money_put moneypunct
Locale-specific facets
ctype_byname codecvt_byname messages_byname collate_byname	time_get_byname time_put_byname numpunct_byname moneypunct_byname
Code conversion facets
codecvt_utf8 (C++11) codecvt_utf16 (C++11)	codecvt_utf8_utf16 (C++11) codecvt_mode (C++11)
C locale
setlocale localeconv lconv	LC_ALLLC_COLLATELC_CTYPELC_MONETARYLC_NUMERICLC_TIME

std::wstring_convert

Member functions

wstring_convert::wstring_convert

wstring_convert::~wstring_convert

wstring_convert::from_bytes

wstring_convert::to_bytes

wstring_convert::converted

wstring_convert::state

Defined in header <locale>
template< class Codecvt, class Elem = wchar_t, class Wide_alloc = std::allocator<Elem>, class Byte_alloc = std::allocator<char> > class wstring_convert;		(since C++11) (deprecated in C++17)

Class template std::wstring_convert performs conversions between byte string std::string and wide string std::basic_string<Elem>, using an individual code conversion facet Codecvt. std::wstring_convert assumes ownership of the conversion facet, and cannot use a facet managed by a locale. The standard facets suitable for use with std::wstring_convert are std::codecvt_utf8 for UTF-8/UCS2 and UTF-8/UCS4 conversions and std::codecvt_utf8_utf16 for UTF-8/UTF-16 conversions.

Member types

Member type	Definition
byte_string	std::basic_string<char, char_traits<char>, Byte_alloc>
wide_string	std::basic_string<Elem, char_traits<Elem>, Wide_alloc>
state_type	Codecvt::state_type
int_type	wide_string::traits_type::int_type

Member functions

(constructor)	constructs a new wstring_convert (public member function)
operator=	the copy assignment operator is deleted (public member function)
(destructor)	destructs the wstring_convert and its conversion facet (public member function)
from_bytes	converts a byte string into a wide string (public member function)
to_bytes	converts a wide string into a byte string (public member function)
converted	returns the number of characters successfully converted (public member function)
state	returns the current conversion state (public member function)

See also

Character conversions	locale-defined multibyte (UTF-8, GB18030)	UTF-8	UTF-16
UTF-16	mbrtoc16 / c16rtomb(with C11's DR488)	codecvt<char16_t, char, mbstate_t> codecvt_utf8_utf16<char16_t> codecvt_utf8_utf16<char32_t> codecvt_utf8_utf16<wchar_t>	N/A
UCS2	c16rtomb(without C11's DR488)	codecvt_utf8<char16_t> codecvt_utf8<wchar_t>(Windows)	codecvt_utf16<char16_t> codecvt_utf16<wchar_t>(Windows)
UTF-32	mbrtoc32 / c32rtomb	codecvt<char32_t, char, mbstate_t> codecvt_utf8<char32_t> codecvt_utf8<wchar_t>(non-Windows)	codecvt_utf16<char32_t> codecvt_utf16<wchar_t>(non-Windows)
system wide: UTF-32(non-Windows) UCS2(Windows)	mbsrtowcs / wcsrtombs use_facet<codecvt <wchar_t, char, mbstate_t>>(locale)	No	No

wbuffer_convert (C++11)(deprecated in C++17)	performs conversion between a byte stream buffer and a wide stream buffer (class template)
codecvt_utf8 (C++11)(deprecated in C++17)	converts between UTF-8 and UCS2/UCS4 (class template)
codecvt_utf8_utf16 (C++11)(deprecated in C++17)	converts between UTF-8 and UTF-16 (class template)