_ultoa, _ultow

發行項
01/04/2008

Convert an unsigned long integer to a string. More secure versions of these functions are available; see _ultoa_s, _ultow_s.

char *_ultoa(
   unsigned long value,
   char *str,
   int radix 
);
wchar_t *_ultow(
   unsigned long value,
   wchar_t *str,
   int radix 
);
template <size_t size>
char *_ultoa(
   unsigned long value,
   char (&str)[size],
   int radix 
); // C++ only
template <size_t size>
wchar_t *_ultow(
   unsigned long value,
   wchar_t (&str)[size],
   int radix 
); // C++ only

Parameters

value
Number to be converted.
str
String result.
radix
Base of value*.*

Return Value

Each of these functions returns a pointer to str. There is no error return.

Remarks

The _ultoa function converts value to a null-terminated character string and stores the result (up to 33 bytes) in str. 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.

Security Note:
To prevent buffer overruns, ensure that the str buffer is large enough to hold the converted digits plus the trailing null-character.

In C++, these functions have template overloads that invoke the newer, secure counterparts of these functions. For more information, see Secure Template Overloads.

Generic-Text Routine Mappings

TCHAR.H routine	_UNICODE & _MBCS not defined	_MBCS defined	_UNICODE defined
_ultot	_ultoa	_ultoa	_ultow

Requirements

Routine	Required header
_ultoa	<stdlib.h>
_ultow	<stdlib.h> or <wchar.h>

For additional compatibility information, see Compatibility in the Introduction.

Example

See the example for _itoa.

.NET Framework Equivalent

System::Convert::ToString

共用方式為