isalpha, iswalpha

Visual Studio 6.0

int isalpha( int c );

int iswalpha( wint_t c );

Each of these routines returns true if c is a particular representation of an alphabetic character.

Routine Required Header Compatibility
isalpha <ctype.h> ANSI, Win 95, Win NT
iswalpha <ctype.h> or <wchar.h> ANSI, Win 95, Win NT

For additional compatibility information, see Compatibility in the Introduction.


LIBC.LIB Single thread static library, retail version
LIBCMT.LIB Multithread static library, retail version
MSVCRT.LIB Import library for MSVCRT.DLL, retail version

Return Value

isalpha returns a non-zero value if c is within the ranges A – Z or a – z. iswalpha returns a non-zero value only for wide characters for which iswupper or iswlower is true, that is, for any wide character that is one of an implementation-defined set for which none of iswcntrl, iswdigit, iswpunct, or iswspace is true. Each of these routines returns 0 if c does not satisfy the test condition.

The result of the test condition for the isalpha function depends on the LC_CTYPE category setting of the current locale; see setlocale for more information. For iswalpha, the result of the test condition is independent of locale.



Integer to test

Generic-Text Routine Mappings

TCHAR.H Routine _UNICODE & _MBCS Not Defined _MBCS Defined _UNICODE Defined
_istalpha isalpha _ismbcalpha iswalpha

Character Classification RoutinesLocale Routinesis, isw Function Overview