Namespaces
Variants
Actions

iswalpha

From cppreference.com
< c‎ | string‎ | wide
 
 
 
Null-terminated wide strings
Functions
Character classification
(C95)
iswalpha
(C95)
(C95)
(C95)
(C95)
(C95)  
(C99)
(C95)
(C95)
(C95)
(C95)
(C95)
(C95)
(C95)
Character manipulation
(C95)
(C95)
(C95)
(C95)
Conversions to numeric formats
(C95)(C99)
(C99)(C95)(C99)
(C95)(C99)
(C99)(C99)    

String manipulation
(C95)(C11)
(C95)(C11)
(C95)
(C95)(C11)
(C95)(C11)

String examination
(C95)(C11)
(C95)
(C95)
(C95)
(C95)
(C95)
(C95)
(C95)
(C95)
(C95)
(C95)(C11)

Array manipulation
(C95)(C11)
(C95)(C11)  
(C95)
(C95)
(C95)

Types Macros
(C95)
 
Defined in header <wctype.h>
int iswalpha( wint_t ch );
(since C95)

Checks if the given wide character is an alphabetic character, i.e. either an uppercase letter (ABCDEFGHIJKLMNOPQRSTUVWXYZ), a lowercase letter (abcdefghijklmnopqrstuvwxyz) or any alphabetic character specific to the current locale.

Contents

[edit] Parameters

ch - wide character

[edit] Return value

Non-zero value if the wide character is an alphabetic character, zero otherwise.

[edit] Notes

ISO 30112 specifies which Unicode characters are include in POSIX alpha category.

[edit] Example

Run this code
#include <locale.h>
#include <stdio.h>
#include <wchar.h>
#include <wctype.h>
 
int main(void)
{
 wchar_t c = L'\u0b83'; // Tamil sign Visarga ('ஃ')
 printf ("in the default locale, iswalpha(%#x) = %d\n", c, !!iswalpha(c));
 setlocale (LC_ALL, "en_US.utf8");
 printf ("in Unicode locale, iswalpha(%#x) = %d\n", c, !!iswalpha(c));
}

Possible output: 

in the default locale, iswalpha(0xb83) = 0
in Unicode locale, iswalpha(0xb83) = 1

[edit] References

  • C23 standard (ISO/IEC 9899:2024):
  • TBD The iswalpha function (p: TBD)
  • C17 standard (ISO/IEC 9899:2018):
  • 7.30.2.1.2 The iswalpha function (p: 327)
  • C11 standard (ISO/IEC 9899:2011):
  • 7.30.2.1.2 The iswalpha function (p: 448-449)
  • C99 standard (ISO/IEC 9899:1999):
  • 7.25.2.1.2 The iswalpha function (p: 394-395)

[edit] See also

checks if a character is alphabetic
(function) [edit]
C++ documentation for iswalpha
ASCII values characters

iscntrl
iswcntrl

isprint
iswprint

isspace
iswspace

isblank
iswblank

isgraph
iswgraph

ispunct
iswpunct

isalnum
iswalnum

isalpha
iswalpha

isupper
iswupper

islower
iswlower

isdigit
iswdigit

isxdigit
iswxdigit

decimal hexadecimal octal
0–8 \x0–\x8 0円–10円 control codes (NUL, etc.) ≠0 0 0 0 0 0 0 0 0 0 0 0
9 \x9 11円 tab (\t) ≠0 0 ≠0 ≠0 0 0 0 0 0 0 0 0
10–13 \xA–\xD 12円–15円 whitespaces (\n, \v, \f, \r) ≠0 0 ≠0 0 0 0 0 0 0 0 0 0
14–31 \xE–\x1F 16円–37円 control codes ≠0 0 0 0 0 0 0 0 0 0 0 0
32 \x20 40円 space 0 ≠0 ≠0 ≠0 0 0 0 0 0 0 0 0
33–47 \x21–\x2F 41円–57円 !"#$%&'()*+,-./ 0 ≠0 0 0 ≠0 ≠0 0 0 0 0 0 0
48–57 \x30–\x39 60円–71円 0123456789 0 ≠0 0 0 ≠0 0 ≠0 0 0 0 ≠0 ≠0
58–64 \x3A–\x40 72円–100円 :;<=>?@ 0 ≠0 0 0 ≠0 ≠0 0 0 0 0 0 0
65–70 \x41–\x46 101円–106円 ABCDEF 0 ≠0 0 0 ≠0 0 ≠0 ≠0 ≠0 0 0 ≠0
71–90 \x47–\x5A 107円–132円 GHIJKLMNOP
QRSTUVWXYZ 		0 ≠0 0 0 ≠0 0 ≠0 ≠0 ≠0 0 0 0
91–96 \x5B–\x60 133円–140円 [\]^_` 0 ≠0 0 0 ≠0 ≠0 0 0 0 0 0 0
97–102 \x61–\x66 141円–146円 abcdef 0 ≠0 0 0 ≠0 0 ≠0 ≠0 0 ≠0 0 ≠0
103–122 \x67–\x7A 147円–172円 ghijklmnop
qrstuvwxyz 		0 ≠0 0 0 ≠0 0 ≠0 ≠0 0 ≠0 0 0
123–126 \x7B–\x7E 173円–176円 {|}~ 0 ≠0 0 0 ≠0 ≠0 0 0 0 0 0 0
127 \x7F 177円 backspace character (DEL) ≠0 0 0 0 0 0 0 0 0 0 0 0

AltStyle によって変換されたページ (->オリジナル) /