std::iswxdigit
From cppreference.com
                    
                                        
                    
                    
                                                            
                    |   Defined in header  <cwctype>
  | 
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|   int iswxdigit( wint_t ch );  | 
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Checks if the given wide character corresponds (if narrowed) to a hexadecimal numeric character, i.e. one of 0123456789abcdefABCDEF.
If the value of ch is neither representable as a wchar_t nor equal to the value of the macro WEOF, the behavior is undefined.
Parameters
| ch | - | wide character | 
Return value
Non-zero value if the wide character is a hexadecimal numeric character, zero otherwise.
Notes
std::iswdigit and std::iswxdigit are the only standard wide character classification functions that are not affected by the currently installed C locale.
Example
Run this code
#include <cwctype> #include <iostream> int main() { std::cout << std::boolalpha << (std::iswxdigit(L'a') != 0) << ' ' << (std::iswxdigit(L'ä') != 0) << '\n'; }
Output:
true false
See also
|   checks if a character is classified as a hexadecimal digit by a locale  (function template)  | |
|   checks if a character is a hexadecimal character  (function)  | |
|   C documentation for iswxdigit 
 | |
| ASCII values | characters | 
 isxdigit  | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| decimal | hexadecimal | octal | |||||||||||||
| 0–8 | \x0–\x8
 | 
\0–\10
 | 
control codes (NUL, etc.)
 | 
≠0
 | 
 0
 | 
 0
 | 
 0
 | 
 0
 | 
 0
 | 
 0
 | 
 0
 | 
 0
 | 
 0
 | 
 0
 | 
 0
 | 
| 9 | \x9
 | 
\11
 | 
tab (\t)
 | 
≠0
 | 
 0
 | 
≠0
 | 
≠0
 | 
 0
 | 
 0
 | 
 0
 | 
 0
 | 
 0
 | 
 0
 | 
 0
 | 
 0
 | 
| 10–13 | \xA–\xD
 | 
\12–\15
 | 
whitespaces (\n, \v, \f, \r)
 | 
≠0
 | 
 0
 | 
≠0
 | 
 0
 | 
 0
 | 
 0
 | 
 0
 | 
 0
 | 
 0
 | 
 0
 | 
 0
 | 
 0
 | 
| 14–31 | \xE–\x1F
 | 
\16–\37
 | 
control codes | ≠0
 | 
 0
 | 
 0
 | 
 0
 | 
 0
 | 
 0
 | 
 0
 | 
 0
 | 
 0
 | 
 0
 | 
 0
 | 
 0
 | 
| 32 | \x20
 | 
\40
 | 
space |  0
 | 
≠0
 | 
≠0
 | 
≠0
 | 
 0
 | 
 0
 | 
 0
 | 
 0
 | 
 0
 | 
 0
 | 
 0
 | 
 0
 | 
| 33–47 | \x21–\x2F
 | 
\41–\57
 | 
!"#$%&'()*+,-./
 | 
 0
 | 
≠0
 | 
 0
 | 
 0
 | 
≠0
 | 
≠0
 | 
 0
 | 
 0
 | 
 0
 | 
 0
 | 
 0
 | 
 0
 | 
| 48–57 | \x30–\x39
 | 
\60–\71
 | 
0123456789
 | 
 0
 | 
≠0
 | 
 0
 | 
 0
 | 
≠0
 | 
 0
 | 
≠0
 | 
 0
 | 
 0
 | 
 0
 | 
≠0
 | 
≠0
 | 
| 58–64 | \x3A–\x40
 | 
\72–\100
 | 
:;<=>?@
 | 
 0
 | 
≠0
 | 
 0
 | 
 0
 | 
≠0
 | 
≠0
 | 
 0
 | 
 0
 | 
 0
 | 
 0
 | 
 0
 | 
 0
 | 
| 65–70 | \x41–\x46
 | 
\101–\106
 | 
ABCDEF
 | 
 0
 | 
≠0
 | 
 0
 | 
 0
 | 
≠0
 | 
 0
 | 
≠0
 | 
≠0
 | 
≠0
 | 
 0
 | 
 0
 | 
≠0
 | 
| 71–90 | \x47–\x5A
 | 
\107–\132
 | 
GHIJKLMNOPQRSTUVWXYZ
 | 
 0
 | 
≠0
 | 
 0
 | 
 0
 | 
≠0
 | 
 0
 | 
≠0
 | 
≠0
 | 
≠0
 | 
 0
 | 
 0
 | 
 0
 | 
| 91–96 | \x5B–\x60
 | 
\133–\140
 | 
[\]^_`
 | 
 0
 | 
≠0
 | 
 0
 | 
 0
 | 
≠0
 | 
≠0
 | 
 0
 | 
 0
 | 
 0
 | 
 0
 | 
 0
 | 
 0
 | 
| 97–102 | \x61–\x66
 | 
\141–\146
 | 
abcdef
 | 
 0
 | 
≠0
 | 
 0
 | 
 0
 | 
≠0
 | 
 0
 | 
≠0
 | 
≠0
 | 
 0
 | 
≠0
 | 
 0
 | 
≠0
 | 
| 103–122 | \x67–\x7A
 | 
\147–\172
 | 
ghijklmnopqrstuvwxyz
 | 
 0
 | 
≠0
 | 
 0
 | 
 0
 | 
≠0
 | 
 0
 | 
≠0
 | 
≠0
 | 
 0
 | 
≠0
 | 
 0
 | 
 0
 | 
| 123–126 | \x7B–\x7E
 | 
\172–\176
 | 
{|}~
 | 
 0
 | 
≠0
 | 
 0
 | 
 0
 | 
≠0
 | 
≠0
 | 
 0
 | 
 0
 | 
 0
 | 
 0
 | 
 0
 | 
 0
 | 
| 127 | \x7F
 | 
\177
 | 
backspace character (DEL)
 | 
≠0
 | 
 0
 | 
 0
 | 
 0
 | 
 0
 | 
 0
 | 
 0
 | 
 0
 | 
 0
 | 
 0
 | 
 0
 | 
 0
 |