std::wstring_convert::wstring_convert

 

C++

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)

 

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 ctype_byname<char> 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_ALL LC_COLLATE LC_CTYPE LC_MONETARY LC_NUMERIC LC_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

 

wstring_convert( Codecvt* pcvt = new Codecvt );	(1)
wstring_convert( Codecvt* pcvt, state_type state);	(2)
wstring_convert( const byte_string& byte_err, const wide_string& wide_err = wide_string() );	(3)

1) Constructs the wstring_convert object with a specified conversion facet, using default-constructed values for the shift state and the error strings

2) Constructs the wstring_convert object with a specified conversion facet and specified shift state, using default-constructed values for the error strings

3) Constructs the wstring_convert object with specified error strings, using new Codecvt as the conversion facet and the default-constructed state_type as shift state.

Parameters

pcvt	-	pointer to the conversion facet of type Codecvt
state	-	initial value of the conversion shift state
byte_err	-	narrow string to display on errors
wide_err	-	wide string to display on errors

Example

#include <locale>
#include <utility>
#include <codecvt>
 
// utility wrapper to adapt locale-bound facets for wstring/wbuffer convert
template<class Facet>
struct deletable_facet : Facet
{
    template<class ...Args>
    deletable_facet(Args&& ...args) : Facet(std::forward<Args>(args)...) {}
    ~deletable_facet() {}
};
 
int main()
{
    // UTF-16le / UCS4 conversion
    std::wstring_convert<std::codecvt_utf16<char32_t, 0x10ffff, std::little_endian>> u16to32;
 
    // UTF-8 / wide string conversion with custom messages
    std::wstring_convert<std::codecvt_utf8<wchar_t>> u8towide("Error!", L"Error!");
 
    // GB18030 / wide string conversion facet
    typedef deletable_facet<std::codecvt_byname<wchar_t, char, std::mbstate_t>> F;
    std::wstring_convert<F> gbtowide(new F("zh_CN.gb18030"));
}