_itoa, _i64toa, _ui64toa, _itow, _i64tow, _ui64tow
Convert an integer to a string.
char*_itoa(intvalue**,char*string,intradix);**
char *_i64toa(__int64value**,char*string,intradix);**
char*_ui64toa(unsigned_int64value**,char*string,intradix);**
wchar_t*_itow(intvalue**,wchar_t*string,intradix);**
wchar_t*_i64tow(__int64value**,wchar_t*string,intradix);**
wchar_t*_ui64tow(unsigned __int64value**,wchar_t*string,intradix);**
| Routine | Required Header | Compatibility |
| _itoa | <stdlib.h> | Win 95, Win NT |
| _i64toa | <stdlib.h> | Win 95, Win NT |
| _ui64toa | <stdlib.h> | Win 95, Win NT |
| _itow | <stdlib.h> | Win 95, Win NT |
| _i64tow | <stdlib.h> | Win 95, Win NT |
| _ui64tow | <stdlib.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; must be in the range 2 – 36
Remarks
The _itoa, _i64toa, and _ui64toa function convert the digits of the given value argument to a null-terminated character string and stores the result (up to 33 bytes) in string. If radix equals 10 and value is negative, the first character of the stored string is the minus sign ( – ). _itow, _i64tow, and _ui64tow are wide-character versions of _itoa, _i64toa, and _ui64toa respectively.
Generic-Text Routine Mappings
| TCHAR.H Routine | _UNICODE & _MBCS Not Defined | _MBCS Defined | _UNICODE Defined |
| _itot | _itoa | _itoa | _itow |
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