std::btowc - cppreference.com (original) (raw)

Widens a single-byte character c to its wide character equivalent.

Most multibyte character encodings use single-byte codes to represent the characters from the ASCII character set. This function may be used to convert such characters to wchar_t.

[edit] Parameters

[edit] Return value

WEOF if c is EOF.

Wide character representation of c if (unsigned char)c is a valid single-byte character in the initial shift state, WEOF otherwise.

[edit] Example

#include #include #include   void try_widen(char c) { std::wint_t w = std::btowc(c); if (w != WEOF) std::cout << "The single-byte character " << +(unsigned char)c << " widens to " << +w << '\n'; else std::cout << "The single-byte character " << +(unsigned char)c << " failed to widen\n"; }   int main() { std::setlocale(LC_ALL, "lt_LT.iso88594"); std::cout << std::hex << std::showbase << "In Lithuanian ISO-8859-4 locale:\n"; try_widen('A'); try_widen('\xdf'); // German letter ß (U+00df) in ISO-8859-4 try_widen('\xf9'); // Lithuanian letter ų (U+0173) in ISO-8859-4   std::setlocale(LC_ALL, "lt_LT.utf8"); std::cout << "In Lithuanian UTF-8 locale:\n"; try_widen('A'); try_widen('\xdf'); try_widen('\xf9'); }

Possible output:

In Lithuanian ISO-8859-4 locale: The single-byte character 0x41 widens to 0x41 The single-byte character 0xdf widens to 0xdf The single-byte character 0xf9 widens to 0x173 In Lithuanian UTF-8 locale: The single-byte character 0x41 widens to 0x41 The single-byte character 0xdf failed to widen The single-byte character 0xf9 failed to widen

[edit] See also

| | narrows a wide character to a single-byte narrow character, if possible (function) [edit] | | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | | converts a character or characters from char to CharT (virtual protected member function of std::ctype) [edit] | | |