std::codecvt_utf8 – cppreference.com

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definiert in Header `<codecvt>`

`template< class Elem, unsigned long Maxcode = 0x10ffff, std::codecvt_mode Mode = (std::codecvt_mode)0 > class codecvt_utf8 : public std::codecvt<Elem, char, std::mbstate_t>;`

std::codecvt_utf8 ist ein std::codecvt Facette, die Konvertierung zwischen einer UTF-8-codierte Bytefolge und UCS2 oder UCS4 Zeichenkette (abhängig von der Art der Elem) kapselt. Diese codecvt Facette kann verwendet werden, um lesen und schreiben UTF-8-Dateien, sowohl Text und binäre werden .

Original:

std::codecvt_utf8 is a std::codecvt facet which encapsulates conversion between a UTF-8 encoded byte string and UCS2 or UCS4 character string (depending on the type of Elem). This codecvt facet can be used to read and write UTF-8 files, both text and binary.

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Template-Parameter

Elem	-	entweder `char16_t`, `char32_t` oder `wchar_t` Original: either `char16_t`, `char32_t`, or `wchar_t` The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
Maxcode	-	der größte Wert von `Elem` daß diese Facette liest oder ohne Fehler zu schreiben Original: the largest value of `Elem` that this facet will read or write without error The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
Mode	-	eine Konstante vom Typ std::codecvt_mode Original: a constant of type std::codecvt_mode The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

Inherited from std::codecvt

Member types


Mitglied Typ Original: Member type The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.	Definition

`intern_type`	`internT`

`extern_type`	`externT`

`state_type`	`stateT`

Member objects


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

`id` (statisch)	std::locale::id

Member functions


out	Beruft `do_out` Original: invokes `do_out` The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (öffentliche Elementfunktion of `std::codecvt`) [edit]

in	Beruft `do_in` Original: invokes `do_in` The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (öffentliche Elementfunktion of `std::codecvt`) [edit]

unshift	Beruft `do_unshift` Original: invokes `do_unshift` The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (öffentliche Elementfunktion of `std::codecvt`) [edit]

encoding	Beruft `do_encoding` Original: invokes `do_encoding` The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (öffentliche Elementfunktion of `std::codecvt`) [edit]

always_noconv	Beruft `do_always_noconv` Original: invokes `do_always_noconv` The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (öffentliche Elementfunktion of `std::codecvt`) [edit]

length	Beruft `do_length` Original: invokes `do_length` The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (öffentliche Elementfunktion of `std::codecvt`) [edit]

max_length	Beruft `do_max_length` Original: invokes `do_max_length` The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (öffentliche Elementfunktion of `std::codecvt`) [edit]

Protected member functions


do_out [virtuell]	wandelt eine Zeichenkette aus Internt zu externT, wie beim Schreiben in eine Datei Original: converts a string from internT to externT, such as when writing to file The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (virtuellen geschützten Member-Funktion of `std::codecvt`) [edit]

do_in [virtuell]	wandelt eine Zeichenkette aus externT um Internt wie beim Lesen aus Datei 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. (virtuellen geschützten Member-Funktion of `std::codecvt`) [edit]

do_unshift [virtuell]	generiert die Beendigung Ziffernfolge externT Zeichen für unvollständige Umsetzung Original: generates the termination character sequence of externT characters for incomplete conversion The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (virtuellen geschützten Member-Funktion of `std::codecvt`) [edit]

do_encoding [virtuell]	gibt die Anzahl der externT Zeichen notwendig, um ein Internt Charakter zu produzieren, wenn konstant Original: returns the number of externT characters necessary to produce one internT character, if constant The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (virtuellen geschützten Member-Funktion of `std::codecvt`) [edit]

do_always_noconv [virtuell]	testet, ob der Facette kodiert eine Identität Konvertierung für alle gültiges Argument Werte Original: tests if the facet encodes an identity conversion for all valid argument values The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (virtuellen geschützten Member-Funktion of `std::codecvt`) [edit]

do_length [virtuell]	berechnet die Länge der Zeichenfolge, externT durch Umwandlung in gegebenen Internt Puffer verbraucht würde Original: calculates the length of the externT string that would be consumed by conversion into given internT buffer The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (virtuellen geschützten Member-Funktion of `std::codecvt`) [edit]

do_max_length [virtuell]	gibt die maximale Anzahl von externT Zeichen, die in einem einzigen Internt Zeichen umgewandelt werden konnte Original: returns the maximum number of externT characters that could be converted into a single internT character The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (virtuellen geschützten Member-Funktion of `std::codecvt`) [edit]

Inherited from std::codecvt_base


Mitglied Typ Original: Member type The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.	Definition

`enum result { ok, partial, error, noconv };`	Ohne Bereichseinschränkung Aufzählungstyp Original: Unscoped enumeration type The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.


Enumeration konstant Original: Enumeration constant The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.	Definition

`ok`	Umwandlung wurde ohne Fehler beendet Original: conversion was completed with no error The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

`partial`	nicht alle Quellzeichen umgewandelt wurden Original: not all source characters were converted The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

`error`	hat eine ungültige Zeichen Original: encountered an invalid character The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

`noconv`	kein Umbau erforderlich, Eingabe und Ausgabe-Typen sind die gleichen Original: no conversion required, input and output types are the same The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

Beispiel

Das folgende Beispiel demonstriert den Unterschied zwischen UCS2/UTF-8 und UTF-16/UTF-8 Konvertierungen: das dritte Zeichen in der Zeichenfolge ist keine gültige UCS2 Charakter .

Original:

The following example demonstrates the difference between UCS2/UTF-8 and UTF-16/UTF-8 conversions: the third character in the string is not a valid UCS2 character.

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#include <iostream>
#include <string>
#include <locale>
#include <codecvt>
int main()
{
    // UTF-8 data. The character U+1d10b, musical sign segno, does not fit in UCS2
    std::string utf8 = u8"z\u6c34\U0001d10b";

    // 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);
    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 / UCS2 standard conversion facet
    std::wstring_convert<std::codecvt_utf8<char16_t>, char16_t> ucs2conv;
    try {
        std::u16string ucs2 = ucs2conv.from_bytes(utf8);
    } catch(const std::range_error& e) {
        std::u16string ucs2 = ucs2conv.from_bytes(utf8.substr(0, ucs2conv.converted()));
        std::cout << "UCS2 failed after producing " << std::dec << ucs2.size()<<" characters:\n";
        for(char16_t c : ucs2)
            std::cout << std::hex << std::showbase << c << '\n';
    }
}

Output:

UTF16 conversion produced 4 code points:
0x7a
0x6c34
0xd834
0xdd0b
UCS2 failed after producing 2 characters:
0x7a
0x6c34

Siehe auch

Character conversions	narrow multibyte (char)	UTF-8 (char)	UTF-16 (char16_t)
UTF-16	`mbrtoc16` / `c16rtomb`	`codecvt`<char16_t, char, mbstate_t> `codecvt_utf8_utf16`<char16_t> `codecvt_utf8_utf16`<char32_t> `codecvt_utf8_utf16`<wchar_t>	N/A
UCS2	No	`codecvt_utf8`<char16_t>	`codecvt_utf16`<char16_t>
UTF-32/UCS4 (char32_t)	`mbrtoc32` / `c32rtomb`	`codecvt`<char32_t, char, mbstate_t> `codecvt_utf8`<char32_t>	`codecvt_utf16`<char32_t>
UCS2/UCS4 (wchar_t)	No	`codecvt_utf8`<wchar_t>	`codecvt_utf16`<wchar_t>
wide (wchar_t)	`codecvt`<wchar_t, char, mbstate_t> `mbsrtowcs` / `wcsrtombs`	No	No


codecvt	Konvertiten zwischen Zeichenkodierungen, inklusive UTF-8, UTF-16, UTF-32 Original: converts between character encodings, including UTF-8, UTF-16, UTF-32 The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (Klassen-Template) [edit]

codecvt_mode (C++11)	Tags zu ändern, das Verhalten der Standard-codecvt Facetten Original: tags to alter behavior of the standard codecvt facets The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (Klasse) [edit]

codecvt_utf16 (C++11)	konvertiert zwischen UTF-16 und UCS2/UCS4 Original: converts between UTF-16 and UCS2/UCS4 The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (Klassen-Template) [edit]

codecvt_utf8_utf16 (C++11)	converts between UTF-8 and UTF-16 (Klassen-Template) [edit]