| Function | Use | .NET Framework equivalent |
| asctime, _wasctime, asctime_s, _wasctime_s | Convert time from type struct tm to character string. The versions of these functions with the _s suffix are more secure. | System::DateTime::ToLongDateString, System::DateTime::ToLongTimeString, System::DateTime::ToShortDateString, System::DateTime::ToShortTimeString, System::DateTime::ToString |
| clock | Return elapsed CPU time for process. | Not applicable. To call the standard C function, use PInvoke. For more information, see Platform Invoke Examples. |
| ctime, _ctime32, _ctime64, _wctime, _wctime32, _wctime64, _ctime_s, _ctime32_s, _ctime64_s, _wctime_s, _wctime32_s, _wctime64_s | Convert time from type time_t, __time32_t or __time64_t to character string. The versions of these functions with the _s suffix are more secure. | System::DateTime::GetDateTimeFormats, System::DateTime::ToString, System::DateTime::ToLongTimeString, System::DateTime::ToShortTimeString |
| difftime, _difftime32, _difftime64 | Compute difference between two times. | System::DateTime::Subtract |
| _ftime, _ftime32, _ftime64,_ftime_s, _ftime32_s, _ftime64_s | Store current system time in variable of type struct _timeb or type struct __timeb64 The versions of these functions with the _s suffix are more secure. | System::DateTime::Now |
| _futime, _futime32, _futime64 | Set modification time on open file | System::IO::File::SetLastAccessTime, System::IO::File::SetLastWriteTime, System::IO::File::SetCreationTime |
| gmtime, _gmtime32, _gmtime64, _gmtime_s, _gmtime32_s, _gmtime64_s | Convert time from type time_t to struct tm or from type __time64_t to struct tm.The versions of these functions with the _s suffix are more secure. | System::DateTime::UtcNow, System::DateTime::ToUniversalTime |
| localtime, _localtime32, _localtime64, localtime_s, _localtime32_s, _localtime64_s | Convert time from type time_t to struct tm or from type __time64_t to struct tmwith local correction. The versions of these functions with the _s suffix are more secure. | System::DateTime::ToLocalTime |
| _mkgmtime, _mkgmtime32, _mkgmtime64 | Convert time to calendar value in Greenwich Mean Time. | System::DateTime::ToUniversalTime |
| mktime, _mktime32, _mktime64 | Convert time to calendar value. | System::DateTime::DateTime |
| _strdate, _wstrdate, _strdate_s, _wstrdate_s | Return current system date as string. The versions of these functions with the _s suffix are more secure. | System::DateTime::Parse |
| strftime, wcsftime, _strftime_l, _wcsftime_l | Format date-and-time string for international use. | System::DateTime::ToLongDateString, System::DateTime::ToLongTimeString, System::DateTime::ToShortDateString, System::DateTime::ToShortTimeString, System::DateTime::ToString |
| _strtime, _wstrtime, _strtime_s, _wstrtime_s | Return current system time as string. The versions of these functions with the _s suffix are more secure. | System::DateTime::ToLongDateString, System::DateTime::ToLongTimeString, System::DateTime::ToShortDateString, System::DateTime::ToShortTimeString, System::DateTime::ToString |
| time, _time32, _time64 | Get current system time as type time_t, __time32_t or as type __time64_t. | Not applicable. To call the standard C function, use PInvoke. For more information, see Platform Invoke Examples. |
| _tzset | Set external time variables from environment time variable TZ. | Not applicable. To call the standard C function, use PInvoke. For more information, see Platform Invoke Examples. |
| _utime, _utime32, _utime64, _wutime, _wutime32, _wutime64 | Set modification time for specified file using either current time or time value stored in structure. | Not applicable. To call the standard C function, use PInvoke. For more information, see Platform Invoke Examples. |