Reference for package '#rtl'

YearSpan

Calculate the approximate number of years between two TDateTime values.

Declaration

Source position: dateutil.inc line 271

  function YearSpan(const ANow: TDateTime; const AThen: TDateTime)
                    : Double;

Description

YearSpan returns the number of years between ANow and AThen, including any fractional parts of a year. This number is an approximation, based on an average number of days of 365.25 per year (average over 4 years).

See also

Name Description
DaySpan Calculate the approximate number of days between two TDateTime values.
HourSpan Calculate the approximate number of hours between two TDateTime values.
MilliSecondSpan Calculate the approximate number of milliseconds between two TDateTime values.
MinuteSpan Calculate the approximate number of minutes between two TDateTime values.
MonthSpan Calculate the approximate number of months between two TDateTime values.
SecondSpan Calculate the approximate number of seconds between two TDateTime values.
WeekSpan Calculate the approximate number of weeks between two TDateTime values.
YearsBetween Calculate the number of whole years between two TDateTime values

Example

Program Example63;
{ This program demonstrates the YearSpan function }
Uses SysUtils,DateUtils;
Procedure Test(ANow,AThen : TDateTime);
begin
 Write('Number of years between ');
 Write(DateToStr(AThen),' and ',DateToStr(ANow));
 Writeln(' : ',YearSpan(ANow,AThen));
end;
Var
  D1,D2 : TDateTime;
Begin
  D1:=Today;
  D2:=Today-364;
  Test(D1,D2);
  D2:=Today-365;
  Test(D1,D2);
  D2:=Today-366;
  Test(D1,D2);
  D2:=Today-390;
  Test(D1,D2);
  D2:=Today-368;
  Test(D1,D2);
  D2:=Today-1000;
  Test(D1,D2);
End.