On 2015-05-27 09:17, Michael Schnell wrote: > To me (being born 12/31) it's funny that that the base is not a 1/1, > especially 1/1/0001. But of course this is completely irrelevant.
TDateTime's value of 0 being 1899-12-30 is something Borland adopted from Microsoft to be compatible with Microsoft's Excel or Access. And in turn Microsoft Excel tried to be compatible with Lotus 1-2-3. Back in the 90's I searched the internet for the explanation, but can't remember the details any more. A quick google search now revealed this page, though it doesn't go into much detail. "It appears that the reason for Delphi starting at 30 Dec 1899 is to make it as compatible as possible with Excel while at the same time not adopting Excel's incorrectness about dates." [http://www.delphibasics.co.uk/RTL.asp?Name=TDateTime] Do an internet search for "Microsoft date starts at 1899-12-30" and you'll find a lot more information. Regards, - Graeme - -- fpGUI Toolkit - a cross-platform GUI toolkit using Free Pascal http://fpgui.sourceforge.net/ -- _______________________________________________ Lazarus mailing list Lazarus@lists.lazarus.freepascal.org http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus