C++中字符串与数值间的相互转换

将字符串转换为int类型

CString str(_T("381"));
int data = _wtoi(str);

将字符串转换为双精度

注：Unicode下可使用_wtof。不过最好使用_tstof，它实际上是宏，在不同的字符集下解释不同。这样两种字符集都可以编译通过。

CString str(_T("381.33"));
double Text = _tstof(str);

MSDN中关于数据转换的资料：

Data-Conversion Routines

Routine	Use
atof, _atof_l, _wtof, _wtof_l	Convert string to float
atoi, _atoi_l, _wtoi, _wtoi_l	Convert string to int
_atoi64, _atoi64_l, _wtoi64, _wtoi64_l	Convert string to __int64
atol, _atol_l, _wtol, _wtol_l	Convert string to long
_ecvt, _ecvt_s	Convert double to string of specified length
_fcvt, _fcvt_s	Convert double to string with specified number of digits following decimal point
_gcvt, _gcvt_s	Convert double number to string; store string in buffer
_itoa, _i64toa, _ui64toa, _itow, _i64tow, _ui64tow, _itoa_s, _i64toa_s, _ui64toa_s, _itow_s, _i64tow_s, _ui64tow_s	Convert int or __int64 to string
_ltoa, _ltow, _ltoa_s, _ltow_s	Convert long to string
strtod, _strtod_l, wcstod, _wcstod_l	Convert string to double
strtol, wcstol, _strtol_l, _wcstol_l	Convert string to long integer
strtoul, _strtoul_l, wcstoul, _wcstoul_l	Convert string to unsigned long integer
_ultoa, _ultow, _ultoa_s, _ultow_s	Convert unsigned long to string
atof, _atof_l, _wtof, _wtof_l	Convert wide-character string to a double
atoi, _atoi_l, _wtoi, _wtoi_l	Convert wide-character string to int
_atoi64, _atoi64_l, _wtoi64, _wtoi64_l	Convert wide-character string to __int64
atol, _atol_l, _wtol, _wtol_l	Convert wide-character string to long