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isxdigit, iswxdigit, _isxdigit_l, _iswxdigit_l

Determine if an integer represents character that is a hex digit.

int isxdigit(
   int c 
);
int iswxdigit(
   wint_t c 
);
int _isxdigit_l(
   int c,
   _locale_t locale
);
int _iswxdigit_l(
   wint_t c,
   _locale_t locale
);

Parameters

  • c
    Integer to test.

  • locale
    Locale to use.

Return Value

Each of these routines returns nonzero if c is a particular representation of a hexadecimal digit. isxdigit returns a nonzero value if c is a hexadecimal digit (A – F, a – f, or 0 – 9). iswxdigit returns a nonzero value if c is a wide character that corresponds to a hexadecimal digit character. Each of these routines returns 0 if c does not satisfy the test condition.

For the "C" locale, the iswxdigitfunction does not provide support for Unicode full width hexadecimal characters.

When used with a debug CRT library, isxdigit will display a CRT assert if passed a parameter that is not EOF or in the range of 0 through 0xFF. When used with a debug CRT library, isxdigit will use the parameter as an index into an array, with undefined results if the parameter is not EOF or in the range of 0 through 0xFF.

The versions of these functions with the _l suffix are identical except that they use the locale passed in instead of the current locale for their locale-dependent behavior. For more information, see Locale.

Generic-Text Routine Mappings

TCHAR.H routine

_UNICODE & _MBCS not defined

_MBCS defined

_UNICODE defined

_istxdigit

isxdigit

isxdigit

iswxdigit

Requirements

Routine

Required header

isxdigit

<ctype.h>

iswxdigit

<ctype.h> or <wchar.h>

_isxdigit_l

<ctype.h>

_iswxdigit_l

<ctype.h> or <wchar.h>

For additional compatibility information, see Compatibility in the Introduction.

.NET Framework Equivalent

System::Char::IsNumber

See Also

Reference

Character Classification

Locale

is, isw Routines