Calculer l'age d'une personne

function CalculateAge(Birthday, CurrentDate: TDate): Integer;
var
Month, Day, Year, CurrentYear, CurrentMonth, CurrentDay: Word;
begin
DecodeDate(Birthday, Year, Month, Day);
DecodeDate(CurrentDate, CurrentYear, CurrentMonth, CurrentDay);

if (Year = CurrentYear) and (Month = CurrentMonth) and (Day = CurrentDay) then
begin
Result := 0;
end
else
begin
Result := CurrentYear - Year;
if (Month > CurrentMonth) then
Dec(Result)
else
begin
if Month = CurrentMonth then
if (Day > CurrentDay) then
Dec(Result);
end;
end;
end;

procedure TForm1.Button1Click(Sender: TObject);
begin
ShowMessage(IntToStr(CalculateAge(StrToDate('01/07/1970'), Date)));
end;