std::isalnum(std::locale)
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C++
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Localization library
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| Defined in header <locale>
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| template< class CharT > bool isalnum( CharT ch, const locale& loc ); |
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Checks if the given character is classified as an alphanumeric character by the given locale's std::ctype facet.
Contents |
[edit] Parameters
| ch | - | character |
| loc | - | locale |
[edit] Return value
Returns true if the character is classified as alphanumeric, false otherwise.
[edit] Possible implementation
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); } |
[edit] Example
Demonstrates the use of isalnum() with different locales (OS-specific).
Run this code
#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[edit] See also
| checks if a character is alphanumeric (function) [edit] | |
| checks if a wide character is alphanumeric (function) [edit] |
