std::btowc
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Null-terminated multibyte strings
(C++11)(C++11)
Defined in header
<cwchar>
std::wint_t btowc( int c );
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.
Contents
[edit] Parameters
c
-
single-byte character to widen
[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
Run this code
#include <clocale> #include <cwchar> #include <iostream> 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
[virtual]
CharT (virtual protected member function of
std::ctype<CharT>) [edit]
C documentation for btowc