(Xem phần Chuyển đổi các tài liệu tham khảo phạm vi đa-cell trên trang 14 để biết thêm chi tiết.) Bạn cũng có thể sử dụng chức năng xlfGetCell, với đối số 49, phát hiện nếu một tham chiếu ô là một phần của một mảng. Ngoài sự hữu ích của chức năng này | Example Add-ins and Financial Applications 367 year --count 2 1461 day count - year 365 - year - 1 2 for month JAN month MAR month if m_days month d day - m_days month - 1 return if year 3 if m_days FEB --day day 29 month FEB return for month DEC month if m_days month day break day - m_days month - 1 The above code assumes that the serial day-count is that which Excel stores when using its default 1900 date If your application is critically dependent on dates you should check the status of this setting and convert all incoming and returned dates. The following code samples show how to do this. Note that the exported worksheet function accepts and returns dates as 32-bit integers type J. Note also that the state of Excel will not change during a single call to a function but would need to be checked on every call to be super-safe. In practice this is overkill. bool excel_using_1904_system void cpp_xloper Using1904 initialised to xltypeNil cpp_xloper Arg 20 initialised to xltypeInt Excel4 xlfGetDocument Using1904 1 Arg if bool Using1904 return true return false define DAYS_1900_TO_1904 1462 1-Jan-1904 in 1900 system 4 Excel mistakenly thinks that 1900 was a leap year and therefore the first correct interpretation of a date under this system is 1-Mar-1900 which equates to the value 61. 368 Excel Add-in Development in C C int __stdcall worksheet_date_fn int input_date bool using_1904 excel_using_1904_system if using_1904 input_date DAYS_1900_TO_1904 Do something with the date int result some_date_fn input_date if using_1904 result - DAYS_1900_TO_1904 return result Description Given any date find out if it is a GBD in a given centre or union of centres returning either true or false or information about the date if not a GBD when requested. Prototype xloper stdcall is_gbd double ref_date xl_array hols_array xloper rtn_string Type string RBKP Notes Returns a Boolean a more descriptive string or an error value. The first two arguments are .
