Home Original page

std::iscntrl(std::locale) - cppreference.com

From cppreference.com

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).

#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

checks if a character is a control character
(function) [edit]
checks if a wide character is a control character
(function) [edit]