seemingly complex date time calculations

I have this function that should convert them from Ole to UTC8601 standard, but I don't understand how the integer representations of time seem to work.

Can anyone give me some explanation?

the function is called: RipOf_AfxTmFromOleDate

containing statements as: nDaysAbsolute %= 146097L; Where does the value come from and how is it calculated?

where nDaysAbsolute is a long type.

This app gets values from an Oracle database and sends them to another a开发者_JS百科pplication.

In 400 years, there are 97 leap years.

146097 = 365 * 400 + 97.

Take a look at Julian Day calculations.