std::wstring_convert::to_bytes
cppreference.com
 [] |
Google. . , . , . |
![[]](https://upload.cppreference.com/mwiki/images/3/31/Imbox_notice.png){kind=link}
<metanoindex/>
<tbody> </tbody> byte_string to_bytes( Elem wchar ); |
(1) | |
byte_string to_bytes( const Elem* wptr ); |
(2) | |
byte_string to_bytes( const wide_string& wstr ); |
(3) | |
byte_string to_bytes( const Elem* first, const Elem* last); |
(4) | |
,
codecvt .:
Performs wide to multibyte conversion, using the
codecvt facet supplied at construction.1)
2)
,
wptr, byte_string:
Converts the null-terminated wide character sequence beginning at the wide character pointed to by
wptr, to byte_string3)
str byte_string.4)
[first, last) byte_string , ,
wstring_convert . state() converted():
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()byte_string , . , , wstring_convert, .:
A
byte_string object containing the results of the wide to multibyte conversion. If the conversion failed and there was a user-supplied byte-error string provided to the constructor of this wstring_convert, returns that byte-error string.wstring_convert , std::range_error .:
If this
wstring_convert object was constructed without a user-supplied byte-error string, throws std::range_error on conversion failure.#include <iostream>
#include <string>
#include <locale>
#include <codecvt>
#include <iomanip>
// utility function for output
void hex_print(const std::string& s)
{
std::cout << std::hex << std::setfill('0');
for(unsigned char c : s)
std::cout << std::setw(2) << static_cast<int>(c) << ' ';
std::cout << std::dec << '\n';
}
int main()
{
// wide character data
std::wstring wstr = L"z\u00df\u6c34\U0001d10b"; // or L"z"
// wide to UTF-8
std::wstring_convert<std::codecvt_utf8<wchar_t>> conv1;
std::string u8str = conv1.to_bytes(wstr);
std::cout << "UTF-8 conversion produced " << u8str.size() << " bytes:\n";
hex_print(u8str);
// wide to UTF-16le
std::wstring_convert<std::codecvt_utf16<wchar_t, 0x10ffff, std::little_endian>> conv2;
std::string u16str = conv2.to_bytes(wstr);
std::cout << "UTF-16le conversion produced " << u16str.size() << " bytes:\n";
hex_print(u16str);
}
:
UTF-8 conversion produced 10 bytes:
7a c3 9f e6 b0 b4 f0 9d 84 8b
UTF-16le conversion produced 10 bytes:
7a 00 df 00 34 6c 34 d8 0b dd
.
(public -) | |
| () | |
[virtual] |
internT externT, , (virtual protected std::codecvt -)
|