std::wstring_convert::converted

 

C++

Language

Standard library headers

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)

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>
std::size_t converted() const;

Returns the number of source characters that were processed by the most recent from_bytes() or to_bytes().

Return value

The number of characters consumed by the most recent conversion operation.

Exceptions

(none)	(until C++14)
noexcept specification:   noexcept	(since C++14)

Example

Run this code

#include <iostream>
#include <string>
#include <locale>
#include <codecvt>
int main()
{
    std::string utf8 =  u8"z\u00df\u6c34\U0001d10b"; // or u8"zß水𝄋"
                        // or "\x7a\xc3\x9f\xe6\xb0\xb4\xf0\x9d\x84\x8b";
    std::cout << "original UTF-8 string size: " << utf8.size() << '\n';
 
    // the UTF-8 - UTF-32 standard conversion facet
    std::wstring_convert<std::codecvt_utf8<char32_t>, char32_t> cvt;
 
    // UTF-8 to UTF-32
    std::u32string utf32 = cvt.from_bytes(utf8);
    std::cout << "UTF-32 string size: " << utf32.size() << '\n';
    std::cout << "converted() == " << cvt.converted() << '\n';
    // UTF-32 to UTF-8
    utf8 = cvt.to_bytes(utf32);
    std::cout << "new UTF-8 string size: " << utf8.size() << '\n';
    std::cout << "converted() == " << cvt.converted() << '\n';
}

Output:

original UTF-8 string size: 10
UTF-32 string size: 4
converted() == 10
new UTF-8 string size: 10
converted() == 4

See also

to_bytes	converts a wide string into a byte string (public member function)
from_bytes	converts a byte string into a wide string (public member function)