Convert an unsigned long integer to a string.
char *_ultoa( unsigned long value, char *string, int radix );
wchar_t *_ultow( unsigned long value, wchar_t *string, int radix );
| Routine | Required Header | Compatibility |
| _ultoa | <stdlib.h> | Win 95, Win NT |
| _ultow | <stdlib.h> or <wchar.h> | Win 95, Win NT |
For additional compatibility information, see Compatibility in the Introduction.
Libraries
| LIBC.LIB | Single thread static library, retail version |
| LIBCMT.LIB | Multithread static library, retail version |
| MSVCRT.LIB | Import library for MSVCRT.DLL, retail version |
Return Value
Each of these functions returns a pointer to string. There is no error return.
Parameters
value
Number to be converted
string
String result
radix
Base of value
Remarks
The _ultoa function converts value to a null-terminated character string and stores the result (up to 33 bytes) in string. No overflow checking is performed. radix specifies the base of value; radix must be in the range 2 – 36. _ultow is a wide-character version of _ultoa.
Generic-Text Routine Mappings
| TCHAR.H Routine | _UNICODE & _MBCS Not Defined | _MBCS Defined | _UNICODE Defined |
| _ultot | _ultoa | _ultoa | _ultow |
Example
/* ITOA.C: This program converts integers of various
* sizes to strings in various radixes.
*/
#include <stdlib.h>
#include <stdio.h>
void main( void )
{
char buffer[20];
int i = 3445;
long l = -344115L;
unsigned long ul = 1234567890UL;
_itoa( i, buffer, 10 );
printf( "String of integer %d (radix 10): %s\n", i, buffer );
_itoa( i, buffer, 16 );
printf( "String of integer %d (radix 16): 0x%s\n", i, buffer );
_itoa( i, buffer, 2 );
printf( "String of integer %d (radix 2): %s\n", i, buffer );
_ltoa( l, buffer, 16 );
printf( "String of long int %ld (radix 16): 0x%s\n", l,
buffer );
_ultoa( ul, buffer, 16 );
printf( "String of unsigned long %lu (radix 16): 0x%s\n", ul,
buffer );
}
Output
String of integer 3445 (radix 10): 3445
String of integer 3445 (radix 16): 0xd75
String of integer 3445 (radix 2): 110101110101
String of long int -344115 (radix 16): 0xfffabfcd
String of unsigned long 1234567890 (radix 16): 0x499602d2