std::wbuffer_convert

From Cppreference

Defined in header `<locale>`

template<class Codecvt, class Elem = wchar_t, class Tr = std::char_traits<Elem> > class wbuffer_convert;		(C++11 feature)

std::wbuffer_convert is a wrapper over stream buffer of type std::basic_streambuf<char> which gives it the appearance of std::basic_streambuf<Elem>. All I/O performed through std::wbuffer_convert undergoes character conversion as defined by the facet Codecvt. std::wbuffer_convert assumes ownership of the conversion facet, and cannot use a facet managed by a locale. The standard facets suitable for use with std::wbuffer_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.

#include <iostream>
#include <sstream>
#include <string>
#include <locale>
#include <codecvt>
int main()
{
    // Example 1: wrap a UTF-8 string stream in a UCS4 wbuffer_convert
    //
    // UTF-8 narrow multibyte encoding:
    std::string utf8 = u8"z\u00df\u6c34\U0001d10b";  // or u8"zß水𝄋"
                                               // or "\x7a\xc3\x9f\xe6\xb0\xb4\xf0\x9d\x84\x8b";
    std::istringstream utf8buf(utf8);
    std::wbuffer_convert<std::codecvt_utf8<wchar_t>> conv_in(utf8buf.rdbuf());
    std::wistream ucsbuf(&conv_in);
    std::cout << "Reading from a UTF-8 istringstream via wbuffer_convert produces\n";
    for(wchar_t c; ucsbuf.get(c); )
        std::cout << std::hex << std::showbase << c << '\n';
 
    // Example 2: wrap a UTF-8 aware std::cout in a UCS4 wbuffer_convert to output UCS4
    //
    std::wbuffer_convert<std::codecvt_utf8<wchar_t>> conv_out(std::cout.rdbuf());
    std::wostream out(&conv_out);
    std::cout << "Sending UCS4 data to std::cout via wbuffer_convert:\n";
    out << L"z\u00df\u6c34\U0001d10b\n";
}

Output:

Reading from a UTF-8 istringstream via wbuffer_convert produces
0x7a
0xdf
0x6c34
0x1d10b
Sending UCS4 data to std::cout via wbuffer_convert:
zß水𝄋

[edit] See also

Character conversions	narrow multibyte (char)	UTF-8 (char)	UTF-16 (char16_t)
UTF-16	`mbrtoc16` / `c16rtombr`	`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` / `c32rtombr`	`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> `mbstowcs` / `wcstombs`	No	No

wstring_convert (C++11)

performs conversions between a wide string and a byte string
(class template)

codecvt_utf8 (C++11)

converts between UTF-8 and UCS2/UCS4
(class template)

codecvt_utf8_utf16 (C++11)

converts between UTF-8 and UTF-16
(class template)


Member type	Definition

`state_type`	`Codecvt::state_type`

std::wbuffer_convert

From Cppreference

Contents

[edit] Member types

[edit] Member functions

[edit] Example

[edit] See also