isdigit, iswdigit, _ismbcdigit
Remonter à Ctype.h - Index
Header File
ctype.h, mbstring.h
Category
Classification Routines
Prototype
int isdigit(int c);
int iswdigit(wint_t c);
int _ismbcdigit(unsigned int c);
Description
Tests for decimal-digit character.
isdigit is a macro that classifies ASCII-coded integer values by table lookup. The macro is affected by the current locale’s LC_CTYPE category. For the default C locale, c is a digit (0 to 9).
You can make this macro available as a function by undefining (#undef) it.
Return Value
isdigit returns nonzero if c is a digit.
_ismbcdigit returns true if and only if the argument c is a single-byte representation of an ASCII digit.
Example
#include <stdio.h>
#include <ctype.h>
int main(void)
{
char c = 'C';
if (isdigit(c))
printf("%c is a digit\n",c);
else
printf("%c is not a digit\n",c);
return 0;
}
Portability
POSIX | Win32 | ANSI C | ANSI C++ | |
---|---|---|---|---|
isdigit |
+ |
+ |
+ |
+ |
_ismbcdigit |
+ |
|||
iswdigit |
+ |
+ |
+ |