std::iswctype

 

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iswalnum iswalpha iswlower iswupper iswdigit iswxdigit iswblank (C++11)   wctype iswctype	iswcntrl iswgraph iswspace iswprint iswpunct towlower towupper wctrans towctrans
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wcstolwcstoll (C++11) wcstoulwcstoull (C++11)	wcstofwcstodwcstold (C++11)(C++11) wcstoimaxwcstouimax (C++11)(C++11)
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wcslen wcscpy wcsncpy wcscat wcsncat wcscmp wcscoll wcsncmp	wcsxfrm wcschr wcsrchr wcspbrk wcsspn wcscspn wcsstr wcstok
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Defined in header <cwctype>
int iswctype( std::wint_t wc, std::wctype_t desc );

Classifies the wide character wc using the current C locale's LC_CTYPE category identified by desc.

If the value of wc is neither representable as a wchar_t nor equal to the value of the macro WEOF, the behavior is undefined.

Parameters

wc	-	the wide character to classify
desc	-	the LC_CTYPE category, obtained from a call to std::wctype

Return value

Non-zero if the character wc has the property identified by desc in LC_CTYPE facet of the current C locale, zero otherwise.

Example

Run this code

#include <clocale>
#include <cwctype>
#include <iostream>
 
bool classify(wchar_t wc, const std::string& cat)
{
    return std::iswctype(wc, std::wctype(cat.c_str()));
}
 
int main()
{
    std::setlocale(LC_ALL, "ja_JP.UTF-8");
    std::cout << "The character \u6c34 is...\n";
    for (std::string s : {"digit", "alpha", "space", "cntrl", "jkanji"})
        std::cout << s << "? " << std::boolalpha << classify(L'\u6c34', s) << '\n';
}

Output:

The character 水 is...
digit? false
alpha? true
space? false
cntrl? false
jkanji? true

See also

wctype	looks up a character classification category in the current C locale (function)
C documentation for iswctype