cet/ usa time conversions

[frederic]

dear specialists

 
i am looking for standard procedure  which calculates new york time derived from of central european time.
The procedure should take care of the several summer/wintertime transfers
I expected to find this in lazarus but could not find it.

Is there someone to give an hint?

frederic

[kpeters58]

You will most certainly not find anything that "calculates new york time derived from of central european time"

To convert between Eastern Time and CET look here:

http://wiki.freepascal.org/PascalTZ

[balazsszekely]

@frederic

The difference between CET and NYT is six hours.

Code: [Select]

procedure TForm1.Button1Click(Sender: TObject);
var
  CET, NYT: TDateTime;
begin
  CET := Now;
  NYT := IncHour(CET, -6);
  ShowMessage('Time in Europe: ' + FormatDateTime('DD.MM.YYYY  hh:mm:ss', CET) + sLineBreak +
              'Time in New York: ' + FormatDateTime('DD.MM.YYYY  hh:mm:ss', NYT));
end;

PS: To take into account the daylight saving, please read this: http://delphiforfun.org/programs/math_topics/dstcalc.htm

USA starting in 2007, extended DST to begin on the 2nd Sunday in March (Day of month = 14 - (1+Y*5/4) mod 7) and end on the 1st Sunday in November (Day of month = 7 - (1 + 5*Y/4) mod 7).
For Europe, DST begins on the last Sunday in March (Day of month = 31 - (4+ 5*Y/4 ) mod 7) and ends on the last Sunday in October (Day of month = 31 - (1 + 5*Y/4) mod 7

You have 4 formula. It shouldn't be to difficult to make the necessary adjustments.

[frederic]

thanks for your reactions

it looks that i will use pascalTZ for my application

frederic