Data Conversion

These routines convert data from one form to another. Generally these routines execute faster than conversions you might write. Each routine that begins with a to prefix is implemented as a function and as a macro. See Choosing Between Functions and Macros for information about choosing an implementation.

Data-Conversion Routines

Routine	Use	.NET Framework equivalent
abs	Find absolute value of integer	System::Math::Abs
atof, _atof_l, _wtof, _wtof_l	Convert string to float	System::Convert::ToDouble
atoi, _atoi_l, _wtoi, _wtoi_l	Convert string to int	System::Convert::ToInt32, System::Convert::ToUInt32
_atoi64, _atoi64_l, _wtoi64, _wtoi64_l	Convert string to __int64	System::Convert::ToInt64, System::Convert::ToUInt64
atol, _atol_l, _wtol, _wtol_l	Convert string to long	System::Convert::ToInt64, System::Convert::ToUInt64
_ecvt, _ecvt_s	Convert double to string of specified length	System::Convert::ToString
_fcvt, _fcvt_s	Convert double to string with specified number of digits following decimal point	System::Convert::ToString
_gcvt, _gcvt_s	Convert double number to string; store string in buffer	System::Convert::ToString
_itoa, _i64toa, _ui64toa, _itow, _i64tow, _ui64tow, _itoa_s, _i64toa_s, _ui64toa_s, _itow_s, _i64tow_s, _ui64tow_s	Convert int or __int64 to string	System::Convert::ToString
labs	Find absolute value of long integer	System::Math::Abs
_ltoa, _ltow, _ltoa_s, _ltow_s	Convert long to string	System::Convert::ToString
_mbbtombc, _mbbtombc_l	Convert 1-byte multibyte character to corresponding 2-byte multibyte character	Not applicable. To call the standard C function, use PInvoke. For more information, see Platform Invoke Examples.
_mbcjistojms, _mbcjistojms_l, _mbcjmstojis, _mbcjmstojis_l	Convert Japan Industry Standard (JIS) character to Japan Microsoft (JMS) character	Not applicable. To call the standard C function, use PInvoke. For more information, see Platform Invoke Examples.
_mbcjistojms, _mbcjistojms_l, _mbcjmstojis, _mbcjmstojis_l	Convert JMS character to JIS character	Not applicable. To call the standard C function, use PInvoke. For more information, see Platform Invoke Examples.
_mbctohira, _mbctohira_l, _mbctokata, _mbctokata_l	Convert multibyte character to 1-byte hiragana code	Not applicable. To call the standard C function, use PInvoke. For more information, see Platform Invoke Examples.
_mbctohira, _mbctohira_l, _mbctokata, _mbctokata_l	Convert multibyte character to 1-byte katakana code	Not applicable. To call the standard C function, use PInvoke. For more information, see Platform Invoke Examples.
_mbctombb, _mbctombb_l	Convert 2-byte multibyte character to corresponding 1-byte multibyte character	Not applicable. To call the standard C function, use PInvoke. For more information, see Platform Invoke Examples.
mbstowcs, _mbstowcs_l, mbstowcs_s, _mbstowcs_s_l	Convert sequence of multibyte characters to corresponding sequence of wide characters	Not applicable. To call the standard C function, use PInvoke. For more information, see Platform Invoke Examples.
mbtowc, _mbtowc_l	Convert multibyte character to corresponding wide character	Not applicable. To call the standard C function, use PInvoke. For more information, see Platform Invoke Examples.
strtod, _strtod_l, wcstod, _wcstod_l	Convert string to double	System::Convert::ToDouble
strtol, wcstol, _strtol_l, _wcstol_l	Convert string to long integer	System::Convert::ToInt64
strtoul, _strtoul_l, wcstoul, _wcstoul_l	Convert string to unsignedlong integer	System::Convert::ToUInt64
strxfrm, wcsxfrm, _strxfrm_l, _wcsxfrm_l	Transform string into collated form based on locale-specific information	System::IFormattable::ToString
__toascii	Convert character to ASCII code
tolower, _tolower, towlower, _tolower_l, _towlower_l, _mbctolower, _mbctolower_l, _mbctoupper, _mbctoupper_l	Test character and convert to lowercase if currently uppercase	System::Char::ToLower
tolower, _tolower, towlower, _tolower_l, _towlower_l	Convert character to lowercase unconditionally	System::String::ToLower
toupper, _toupper, towupper, _toupper_l, _towupper_l, _mbctolower, _mbctolower_l, _mbctoupper, _mbctoupper_l	Test character and convert to uppercase if currently lowercase	System::Char::ToUpper
toupper, _toupper, towupper, _toupper_l, _towupper_l	Convert character to uppercase unconditionally	System::String::ToUpper
_ultoa, _ultow, _ultoa_s, _ultow_s	Convert unsignedlong to string	System::Convert::ToString
wcstombs, _wcstombs_l, wcstombs_s, _wcstombs_s_l	Convert sequence of wide characters to corresponding sequence of multibyte characters	Not applicable. To call the standard C function, use PInvoke. For more information, see Platform Invoke Examples.
wctomb, _wctomb_l, wctomb_s, _wctomb_s_l	Convert wide character to corresponding multibyte character	Not applicable. To call the standard C function, use PInvoke. For more information, see Platform Invoke Examples.
atof, _atof_l, _wtof, _wtof_l	Convert wide-character string to a double	System::Convert::ToInt64, System::Convert::ToUInt64, System::Convert::ToSingle, System::Convert::ToDouble
atoi, _atoi_l, _wtoi, _wtoi_l	Convert wide-character string to int	Not applicable. To call the standard C function, use PInvoke. For more information, see Platform Invoke Examples.
_atoi64, _atoi64_l, _wtoi64, _wtoi64_l	Convert wide-character string to __int64	Not applicable. To call the standard C function, use PInvoke. For more information, see Platform Invoke Examples.
atol, _atol_l, _wtol, _wtol_l	Convert wide-character string to long	Not applicable. To call the standard C function, use PInvoke. For more information, see Platform Invoke Examples.

See Also

Concepts

Run-Time Routines by Category