std::iscntrl(std::locale)

 

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Locales and facets   Locales has_facet use_facet locale Facet category base classes ctype_base codecvt_base messages_base time_base money_base ctype facets ctype ctype<char> ctype_byname codecvt codecvt_byname numeric facets num_get num_put numpunct numpunct_byname collate facets collate collate_byname time facets time_get time_put time_get_byname time_put_byname

monetary facets money_get money_put moneypunct moneypunct_byname messages facets messages messages_byname Character classification and conversion Character classification isspace    iscntrl isupper islower    isalpha ispunct isdigit    isxdigit isalnum isblank (C++11) isprint isgraph Character conversions toupper    tolower String and stream conversions wstring_convert (C++11/17/26*) wbuffer_convert (C++11/17/26*) Unicode conversion facets codecvt_utf8 (C++11/17/26*) codecvt_utf16 (C++11/17/26*) codecvt_utf8_utf16 (C++11/17/26*) codecvt_mode (C++11/17/26*) C library locales LC_ALLLC_COLLATELC_CTYPELC_MONETARYLC_NUMERICLC_TIME    setlocale localeconv lconv

 

Defined in header <locale>
template< class CharT > bool iscntrl( CharT ch, const locale& loc );

Checks if the given character is classified as a control character by the given locale's std::ctype facet.

Parameters

ch	-	character
loc	-	locale

Return value

Returns true if the character is classified as a control character, false otherwise.

Possible implementation

template<class CharT> bool iscntrl(CharT ch, const std::locale& loc) { return std::use_facet<std::ctype<CharT>>(loc).is(std::ctype_base::cntrl, ch); }

Example

Demonstrates the use of iscntrl() with different locales (OS-specific).

Run this code

#include <iostream>
#include <locale>
 
int main()
{
    const wchar_t CCH = L'\u0094'; // Destructive Backspace in Unicode
 
    std::locale loc1("C");
    std::cout << "iscntrl(CCH, C locale) returned "
              << std::boolalpha << std::iscntrl(CCH, loc1) << '\n';
 
    std::locale loc2("en_US.UTF8");
    std::cout << "iscntrl(CCH, Unicode locale) returned "
              << std::boolalpha << std::iscntrl(CCH, loc2) << '\n';
}

Possible output:

iscntrl(CCH, C locale) returned false
iscntrl(CCH, Unicode locale) returned true

See also

iscntrl	checks if a character is a control character (function)
iswcntrl	checks if a wide character is a control character (function)