std::wstring_convert::from_bytes

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C++

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Espressioni regolari (C++11)

Operazioni atomicche (C++11)

Multithreading (C++11)

 

Localizzazioni libreria

Impostazioni internazionali e sfaccettature Original: Locales and facets The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
locale
use_facet	has_facet
Carattere classificazione Original: Character classification The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
isspace isblank (C++11) iscntrl isupper islower isalpha	isdigit ispunct isxdigit isalnum isprint isgraph
Conversioni Original: Conversions The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
toupper tolower	wstring_convert (C++11) wbuffer_convert (C++11)
Facet categoria classi di base Original: Facet category base classes The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
ctype_base codecvt_base messages_base	time_base money_base
Facet categorie Original: Facet categories The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
ctype ctype<char> codecvt collate messages time_get time_put	num_get num_put numpunct money_get money_put moneypunct
Locale specifici aspetti Original: Locale-specific facets The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
ctype_byname ctype_byname<char> codecvt_byname messages_byname collate_byname	time_get_byname time_put_byname numpunct_byname moneypunct_byname
Codice di conversione sfaccettature Original: Code conversion facets The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
codecvt_utf8 (C++11) codecvt_utf16 (C++11)	codecvt_utf8_utf16 (C++11) codecvt_mode (C++11)
C locale Original: C locale The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
setlocale localeconv lconv	LC_ALL LC_COLLATE LC_CTYPE LC_MONETARY LC_NUMERIC LC_TIME

 

std::wstring_convert

Membri funzioni Original: Member functions The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

wstring_convert::wstring_convert

wstring_convert::~wstring_convert

wstring_convert::from_bytes

wstring_convert::to_bytes

wstring_convert::converted

wstring_convert::state

 

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Elemento definito nell'header <locale>
wide_string from_bytes( char byte );	(1)
wide_string from_bytes( const char* ptr );	(2)
wide_string from_bytes( const byte_string& str );	(3)
wide_string from_bytes( const char* first, const char* last);	(4)

Esegue multibyte alla conversione di larghezza, con la faccetta codecvt alimentato a costruzione.

Original:

Performs multibyte to wide conversion, using the codecvt facet supplied at construction.

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1)

Converte byte come se fosse una stringa di lunghezza 1 wide_string

Original:

Converts byte as if it was a string of length 1 to wide_string

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2)

Converte il carattere di terminazione Null inizio sequenza multibyte in corrispondenza del carattere puntato da ptr a wide_string

Original:

Converts the null-terminated multibyte character sequence beginning at the character pointed to by ptr to wide_string

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3)

Converte la stringa in stretta str wide_string.

Original:

Converts the narrow string str to wide_string.

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4)

Converte il carattere di stretta [first, last) multibyte sequenza wide_string

Original:

Converts the narrow multibyte character sequence [first, last) to wide_string

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In tutti i casi, la conversione inizia in stato di spostamento iniziale, a meno che non stato iniziale di partenza è stato fornito a questo costruttore wstring_convert. Il numero di caratteri convertiti e il valore finale dello stato di conversione sono ricordati e si può accedere con state() e converted()

Original:

In all cases, the conversion begins in initial shift state, unless non-initial starting state was provided to this wstring_convert constructor. The number of characters converted and the final value of the conversion state are remembered and can be accessed with state() and converted()

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Valore di ritorno

Un oggetto wide_string contenente i risultati di multibyte alla conversione di larghezza. Se la conversione non è riuscita e si è un utente fornita di ampio errore di stringa fornita al costruttore di questo wstring_convert, che restituisce ampio stringa di errore.

Original:

A wide_string object containing the results of multibyte to wide conversion. If the conversion failed and there was a user-supplied wide-error string provided to the constructor of this wstring_convert, returns that wide-error string.

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Eccezioni

Se questo oggetto wstring_convert è stato costruito senza che l'utente fornita ampia stringa di errore, getta std::range_error in caso di errore di conversione.

Original:

If this wstring_convert object was constructed without a user-supplied wide-error string, throws std::range_error on conversion failure.

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Esempio

#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";

    // the UTF-8 / UTF-16 standard conversion facet
    std::wstring_convert<std::codecvt_utf8_utf16<char16_t>, char16_t> utf16conv;
    std::u16string utf16 = utf16conv.from_bytes(utf8.data());
    std::cout << "UTF16 conversion produced " << utf16.size() << " code points:\n";
    for(char16_t c : utf16)
        std::cout << std::hex << std::showbase << c << '\n';

    // the UTF-8 / UTF-32 standard conversion facet
    std::wstring_convert<std::codecvt_utf8<char32_t>, char32_t> utf32conv;
    std::u32string utf32 = utf32conv.from_bytes(utf8);
    std::cout << "UTF32 conversion produced " << std::dec << utf32.size() << " code points:\n";
    for(char32_t c : utf32)
        std::cout << std::hex << std::showbase << c << '\n';
}

Output:

UTF16 conversion produced 5 code points:
0x7a
0xdf
0x6c34
0xd834
0xdd0b
UTF32 conversion produced 4 code points:
0x7a
0xdf
0x6c34
0x1d10b

Vedi anche

to_bytes	converte una stringa larga in una stringa di byte Original: converts a wide string into a byte string The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (metodo pubblico)
mbsrtowcs	converte una stringa di caratteri multibyte stretta alla stringa di larghezza, determinato stato Original: converts a narrow multibyte character string to wide string, given state The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (funzione)
do_in [virtuale]	converte una stringa da externT a internt, come ad esempio durante la lettura dal file Original: converts a string from externT to internT, such as when reading from file The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (virtuale protetto funzione of std::codecvt membro)