Can I display the value of an enum with printf()?
Is there a one-liner that lets me output the current value of an enum?
As a string, no. As an integer, %d.
Unless you count:
static char* enumStrings[] = { /* filler 0's to get to the first value, */
"enum0", "enum1",
/* filler for hole in the middle: ,0 */
"enum2", "enum3", .... };
...
printf("The value is %s\n", enumStrings[thevalue]);
This won't work for something like an enum of bit masks. At that point, you need a hash table or some other more elaborate data structure.
enum MyEnum
{ A_ENUM_VALUE=0,
B_ENUM_VALUE,
C_ENUM_VALUE
};
int main()
{
printf("My enum Value : %d\n", (int)C_ENUM_VALUE);
return 0;
}
You have just to cast enum to int !
Output : My enum Value : 2
The correct answer to this has already been given: no, you can't give the name of an enum, only it's value.
Nevertheless, just for fun, this will give you an enum and a lookup-table all in one and give you a means of printing it by name:
main.c:
#include "Enum.h"
CreateEnum(
EnumerationName,
ENUMValue1,
ENUMValue2,
ENUMValue3);
int main(void)
{
int i;
EnumerationName EnumInstance = ENUMValue1;
/* Prints "ENUMValue1" */
PrintEnumValue(EnumerationName, EnumInstance);
/* Prints:
* ENUMValue1
* ENUMValue2
* ENUMValue3
*/
for (i=0;i<3;i++)
{
PrintEnumValue(EnumerationName, i);
}
return 0;
}
Enum.h:
#include <stdio.h>
#include <string.h>
#ifdef NDEBUG
#define CreateEnum(name,...) \
typedef enum \
{ \
__VA_ARGS__ \
} name;
#define PrintEnumValue(name,value)
#else
#define CreateEnum(name,...) \
typedef enum \
{ \
__VA_ARGS__ \
} name; \
const char Lookup##name[] = \
#__VA_ARGS__;
#define PrintEnumValue(name, value) print_enum_value(Lookup##name, value)
void print_enum_value(const char *lookup, int value);
#endif
Enum.c
#include "Enum.h"
#ifndef NDEBUG
void print_enum_value(const char *lookup, int value)
{
char *lookup_copy;
int lookup_length;
char *pch;
lookup_length = strlen(lookup);
lookup_copy = malloc((1+lookup_length)*sizeof(char));
strcpy(lookup_copy, lookup);
pch = strtok(lookup_copy," ,");
while (pch != NULL)
{
if (value == 0)
{
printf("%s\n",pch);
break;
}
else
{
pch = strtok(NULL, " ,.-");
value--;
}
}
free(lookup_copy);
}
#endif
Disclaimer: don't do this.