Defined in header <locale> | ||
---|---|---|
template< class CharT > bool isalnum( CharT ch, const locale& loc ); |
Checks if the given character classified as an alphanumeric character by the given locale's std::ctype
facet.
ch | - | character |
loc | - | locale |
Returns true
if the character is classified as alphanumeric, false
otherwise.
template< class CharT > bool isalnum( CharT ch, const std::locale& loc ) { return std::use_facet<std::ctype<CharT>>(loc).is(std::ctype_base::alnum, ch); } |
Demonstrates the use of isalnum() with different locales (OS-specific).
#include <iostream> #include <locale> int main() { const wchar_t c = L'\u2135'; // mathematical symbol aleph std::locale loc1("C"); std::cout << "isalnum('ℵ', C locale) returned " << std::boolalpha << std::isalnum(c, loc1) << '\n'; std::locale loc2("en_US.UTF-8"); std::cout << "isalnum('ℵ', Unicode locale) returned " << std::boolalpha << std::isalnum(c, loc2) << '\n'; }
Possible output:
isalnum('ℵ', C locale) returned false isalnum('ℵ', Unicode locale) returned true
checks if a character is alphanumeric (function) |
|
checks if a wide character is alphanumeric (function) |
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