Duration function

function FormatSeconds(TotalSeconds: Double; WholeSecondsOnly: Boolean = True; DisplayAll: Boolean = False): string;
var
  Centuries, Years, Months, Minutes, Hours, Days, Weeks: Word;
  Secs: Double;
  TmpStr: array[1..8] of string;
  SecondsPerCentury: Int64;
  FS: string;
begin
  (** Suppress the decimal part if Whole Seconds Only is desired **)
  if WholeSecondsOnly then
    FS := '%.0f'
  else
    FS := '%.2f';

  (** Split the calculation to avoid an overflow **)
  SecondsPerCentury := 36500 * 24;
  SecondsPerCentury := SecondsPerCentury * 3600;
  SecondsPerCentury := SecondsPerCentury + ({4 Leap years per century} 4 * 24 * 3600);
  (** Get centuries **)
  Centuries := Trunc(TotalSeconds / SecondsPerCentury);
  TotalSeconds := TotalSeconds - (Centuries * SecondsPerCentury);

  (** Get years **)
  Years := Trunc(TotalSeconds / (SecondsPerCentury / 100));
  TotalSeconds := TotalSeconds - (Years * (SecondsPerCentury / 100));

  (** Get months **)
  Months := Trunc(TotalSeconds / (SecondsPerCentury / 1200));
  TotalSeconds := TotalSeconds - (Months * (SecondsPerCentury / 1200));

  (** Get weeks **)
  Weeks := Trunc(TotalSeconds / (24 * 3600 * 7));
  TotalSeconds := TotalSeconds - (Weeks * (24 * 3600 * 7));

  (** Get days **)
  Days := Trunc(TotalSeconds / (24 * 3600));
  TotalSeconds := TotalSeconds - (Days * (24 * 3600));

  (** Get Hours **)
  Hours := Trunc(TotalSeconds / 3600);
  TotalSeconds := TotalSeconds - (Hours * 3600);

  (** Get minutes **)
  Minutes := Trunc(TotalSeconds / 60);
  TotalSeconds := TotalSeconds - (Minutes * 60);

  (** Get seconds **)
  if WholeSecondsOnly then
    Secs := Trunc(TotalSeconds)
  else
    Secs := TotalSeconds;

  (** Deal with single values **)
  if Centuries = 1 then
    TmpStr[1] := ' Century, '
  else
    TmpStr[1] := ' Centuries, ';
  if Years = 1 then
    TmpStr[2] := ' Year, '
  else
    TmpStr[2] := ' Years, ';
  if Months = 1 then
    TmpStr[3] := ' Month, '
  else
    TmpStr[3] := ' Months, ';
  if Weeks = 1 then
    TmpStr[4] := ' Week, '
  else
    TmpStr[4] := ' Weeks, ';
  if Days = 1 then
    TmpStr[5] := ' Day, '
  else
    TmpStr[5] := ' Days, ';
  if Hours = 1 then
    TmpStr[6] := ' Hour, '
  else
    TmpStr[6] := ' Hours, ';
  if Minutes = 1 then
    TmpStr[7] := ' Minute, '
  else
    TmpStr[7] := ' Minutes, ';
  if Secs = 1 then
    TmpStr[8] := ' Second.'
  else
    TmpStr[8] := ' Seconds.';

  if DisplayAll then
    Result := Format('%.0d%s%.0d%s%.0d%s%.0d%s%.0d%s%.0d%s%.0d%s' + FS + '%s', [Centuries, TmpStr[1], Years, TmpStr[2], Months, TmpStr[3], Weeks, TmpStr[4], Days, TmpStr[5], Hours, TmpStr[6], Minutes, TmpStr[7], Secs, TmpStr[8]])
  else
  begin
    if Centuries >= 1 then
    begin
      Result := Format('%.0d%s%.0d%s%.0d%s%.0d%s%.0d%s%.0d%s%.0d%s' + FS + '%s', [Centuries, TmpStr[1], Years, TmpStr[2], Months, TmpStr[3], Weeks, TmpStr[4], Days, TmpStr[5], Hours, TmpStr[6], Minutes, TmpStr[7], Secs, TmpStr[8]]);
      Exit;
    end;

    if Years >= 1 then
    begin
      Result := Format('%.0d%s%.0d%s%.0d%s%.0d%s%.0d%s%.0d%s' + FS + '%s', [Years, TmpStr[2], Months, TmpStr[3], Weeks, TmpStr[4], Days, TmpStr[5], Hours, TmpStr[6], Minutes, TmpStr[7], Secs, TmpStr[8]]);
      Exit;
    end;

    if Months >= 1 then
    begin
      Result := Format('%.0d%s%.0d%s%.0d%s%.0d%s%.0d%s' + FS + '%s', [Months, TmpStr[3], Weeks, TmpStr[4], Days, TmpStr[5], Hours, TmpStr[6], Minutes, TmpStr[7], Secs, TmpStr[8]]);
      Exit;
    end;

    if Weeks >= 1 then
    begin
      Result := Format('%.0d%s%.0d%s%.0d%s%.0d%s' + FS + '%s', [Weeks, TmpStr[4], Days, TmpStr[5], Hours, TmpStr[6], Minutes, TmpStr[7], Secs, TmpStr[8]]);
      Exit;
    end;

    if Days >= 1 then
    begin
      Result := Format('%.0d%s%.0d%s%.0d%s' + FS + '%s', [Days, TmpStr[5], Hours, TmpStr[6], Minutes, TmpStr[7], Secs, TmpStr[8]]);
      Exit;
    end;

    if Hours >= 1 then
    begin
      Result := Format('%.0d%s%.0d%s' + FS + '%s', [Hours, TmpStr[6], Minutes, TmpStr[7], Secs, TmpStr[8]]);
      Exit;
    end;

    if Minutes >= 1 then
    begin
      Result := Format('%.0d%s' + FS + '%s', [Minutes, TmpStr[7], Secs, TmpStr[8]]);
      exit;
    end;

    Result := Format(FS + '%s', [Secs, TmpStr[8]]);
  end;
end;


Jens B

Smukt, takker :)