isdigit
cppreference.com
<tbody>
</tbody>
<ctype.h>
|
||
int isdigit( int ch ); |
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, (0123456789).
, ch unsigned char EOF.
| ch |
, , .
isdigit isxdigit , C, (., Microsoft 1252) .
#include <stdio.h>
#include <ctype.h>
#include <limits.h>
int main(void)
{
for (int ndx=0; ndx<=UCHAR_MAX; ndx++)
if (isdigit(ndx)) printf("%c", ndx);
printf("\n");
}
:
0123456789
- C17 (ISO/IEC 9899:2018):
- 7.4.1.5 isdigit (. 146)
- C11 (ISO/IEC 9899:2011):
- 7.4.1.5 isdigit (. 201)
- C99 (ISO/IEC 9899:1999):
- 7.4.1.5 isdigit (. 182)
- C89/C90 (ISO/IEC 9899:1990):
- 4.3.1.4 isdigit
.
, () | |
C++ isdigit
| |
| ASCII | |||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 08 | \x0\x8
|
\0\10
|
(NUL . .)
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
| 9 | \x9
|
\11
|
(\t)
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
| 1013 | \xA\xD
|
\12\15
|
- (\n, \v, \f, \r)
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
| 1431 | \xE\x1F
|
\16\37
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
| |
| 32 | \x20
|
\40
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
| |
| 3347 | \x21\x2F
|
\41\57
|
!"#$%&'()*+,-./
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
| 4857 | \x30\x39
|
\60\71
|
0123456789
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
| 5864 | \x3A\x40
|
\72\100
|
:;<=>?@
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
| 6570 | \x41\x46
|
\101\106
|
ABCDEF
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
| 7190 | \x47\x5A
|
\107\132
|
GHIJKLMNOPQRSTUVWXYZ
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
| 9196 | \x5B\x60
|
\133\140
|
[\]^_`
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
| 97102 | \x61\x66
|
\141\146
|
abcdef
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
| 103122 | \x67\x7A
|
\147\172
|
ghijklmnopqrstuvwxyz
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
| 123126 | \x7B\x7E
|
\172\176
|
{|}~
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
| 127 | \x7F
|
\177
|
(DEL)
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|