I suspect you want code a bit like examples below I found - its old, and refers to NT/XP but I think its likely to be a good candidate:
http://delphi.about.com/od/delphitips2007/qt/directory_dates.htm # Delphi's FileDateToDateTime converts the system time stamp of a file to a TDateTime value. # FileTimeToSystemTime API converts a 64-bit file time to system time format (TSystemTime) # Delphi's EncodeDateTime returns a TDateTime represented by a specified year, month, day, hour, minute, second, and millisecond. Haven't used the FileTimetoSystemTime API...looks like it converts a file time to system time format. System time is based on Coordinated Universal Time (UTC). below - 86400 is number of seconds in a day. Looks to me times are stored as seconds since 1980 (Windows). However I recall there might be some variants used in NTFS, where the granularity of times stored (less than a second?) is finer than that of FAT32 (~2 seconds). However I am pretty sure the FileDateToDateTime routines do each correctly. [Aside - the different granularities creates subtle problems when copying only modified files from NTFS to FAT32, eg a USB drive. Sometimes the same file is copied again by some routines, even though its the same modified date, see below function xfFilesChanged which includes examples of using both FileDate and DateTime for file modification dates] http://www.efg2.com/Lab/Library/Delphi/DatesAndTimes/index.html Method 3. Alternative for Windows NT -- InstallDate VAR InstallDate: TDateTime; KeyValue : DWORD; Registry : TRegistry; .. . . KeyValue := 0; // 1/1/1980 Registry := TRegistry.Create; TRY Registry.RootKey := HKEY_LOCAL_MACHINE; IF Registry.OpenKeyReadOnly( 'SOFTWARE\Microsoft\Windows NT\CurrentVersion') THEN KeyValue := Registry.ReadInteger('InstallDate'); FINALLY Registry.Free END; // Simiilar to UNIX conversion InstallDate := EncodeDate(1970,1,1) + KeyValue/86400; LabelDateTimeValue.Caption := FormatDateTime('mm/dd/yyyy hh:nn:ss', InstallDate) SysUtils FileGetDate FileGetDate returns a DOS date-time stamp for the specified file. Handle := FileOpen(FileName, fmOpenRead OR fmShareDenyNone); DOSStamp := FileGetDate(Handle); FileClose(Handle); DateTimeStamp := FileDateToDateTime(DOSStamp); function xfFilesChanged(file1: string; file2: string): integer; //check 2 files modification date //returns 0=both files same, 1=file1 later, 2=file2 later //if within 10secs counted as same //note if one file does not exist, returns other as later var fileage1, fileage2: integer; dtdate1, dtdate2, dt10secs: TDateTime; begin result := 0; fileage1 := FileAge(file1); fileage2 := FileAge(file2); if (fileage1 < 0) and (fileage2 > 0) then begin result := 2; exit; end; if (fileage2 < 0) and (fileage1 > 0) then begin result := 1; exit; end; if (fileage1 < 0) or (fileage2 < 0) then exit; //maybe both don't exist dtdate1 := FileDatetoDateTime(fileage1); dtdate2 := FileDatetoDateTime(fileage2); if dtdate1 = dtdate2 then begin result := 0; exit; end; //now if not same, check if within 10 secs //in case of different filesystems dt10secs := encodetime(0, 0, 10, 0); if (dtdate2 > (dtdate1 - dt10secs)) and (dtdate2 < (dtdate1 + dt10secs)) then begin result := 0; exit; end; //still different if dtdate1 > dtdate2 then result := 1 else result := 2; end; John > Okay, thats not a date. Next possibility is something like the win32 > filetime structure. MS uses that for sql date time. Big int representing > 100 nanosec intervals since 1601. There is an API for conversion of > filetime to datetime but cant remember it. (I can do it in SQL but > that's way bad way to go.) > > -- > Phil Scadden, Senior Scientist GNS Science Ltd 764 Cumberland St, > Private Bag 1930, Dunedin, New Zealand Ph +64 3 4799663, fax +64 3 477 > 5232 > > Notice: This email and any attachments are confidential. If received in > error please destroy and immediately notify us. Do not copy or disclose > the contents. > > _______________________________________________ > NZ Borland Developers Group - Delphi mailing list > Post: delphi@delphi.org.nz > Admin: http://delphi.org.nz/mailman/listinfo/delphi > Unsubscribe: send an email to delphi-requ...@delphi.org.nz with Subject: > unsubscribe _______________________________________________ NZ Borland Developers Group - Delphi mailing list Post: delphi@delphi.org.nz Admin: http://delphi.org.nz/mailman/listinfo/delphi Unsubscribe: send an email to delphi-requ...@delphi.org.nz with Subject: unsubscribe
