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.
c | - | wide character to narrow |
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
.
#include <clocale> #include <cwchar> #include <iostream> void try_narrowing(wchar_t c) { int cn = std::wctob(c); if(cn != EOF) std::cout << '\'' << c << "' narrowed to " << +cn << '\n'; else std::cout << '\'' << 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
widens a single-byte narrow character to wide character, if possible (function) |
|
narrows characters (public member function of std::basic_ios<CharT,Traits> ) |
|
invokes do_narrow (public member function of std::ctype<CharT> ) |
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