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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::ToInt32

strtoul, _strtoul_l, wcstoul, _wcstoul_l

Convert string to unsigned long integer

System::Convert::ToUInt32

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

Reference

Run-Time Routines by Category