std::wctob
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Null-terminated multibyte strings
(C++11)(C++11)
Defined in header
<cwchar>
int wctob( std::wint_t c );
Narrows a wide character c if its multibyte character equivalent in the initial shift state is a single byte.
This is typically possible for the characters from the ASCII character set, since most multibyte encodings (such as UTF-8) use single bytes to encode those characters.
Contents
[edit] Parameters
c
-
wide character to narrow
[edit] Return value
EOF if c does not represent a multibyte character with length 1 in initial shift state.
Otherwise, the single-byte representation of c as unsigned char converted to int.
[edit] Example
Run this code
#include <clocale> #include <cwchar> #include <iostream> void try_narrowing(wchar_t c) { int cn = std::wctob(c); if (cn != EOF ) std::cout << '\'' << int(c) << "' narrowed to " << +cn << '\n'; else std::cout << '\'' << int(c) << "' could not be narrowed\n"; } int main() { std::setlocale (LC_ALL, "th_TH.utf8"); std::cout << std::hex << std::showbase << "In Thai UTF-8 locale:\n"; try_narrowing(L'a'); try_narrowing(L'๛'); std::setlocale (LC_ALL, "th_TH.tis620"); std::cout << "In Thai TIS-620 locale:\n"; try_narrowing(L'a'); try_narrowing(L'๛'); }
Output:
In Thai UTF-8 locale: '0x61' narrowed to 0x61 '0xe5b' could not be narrowed In Thai TIS-620 locale: '0x61' narrowed to 0x61 '0xe5b' narrowed to 0xfb
[edit] See also
C documentation for wctob