MonthsBetween

Calculate the number of whole months between two TDateTime values

Declaration

Source position: dateutil.inc line 257

  function MonthsBetween(const ANow: TDateTime; const AThen: TDateTime; 
                        AExact: Boolean) : Integer;

Description

MonthsBetween returns the number of whole months between ANow and AThen. This number is an approximation, based on an average number of days of 30.4375 per month (average over 4 years). This means the fractional part of a month is dropped.

See also

Name Description
DaysBetween Number of whole days between two TDateTime values.
HoursBetween Calculate the number of whole hours between two TDateTime values.
MilliSecondsBetween Calculate the number of whole milliseconds between two TDateTime values.
MinutesBetween Calculate the number of whole minutes between two TDateTime values.
SecondsBetween Calculate the number of whole seconds between two TDateTime values.
WeeksBetween Calculate the number of whole weeks between two TDateTime values
YearsBetween Calculate the number of whole years between two TDateTime values

Example

Program Example56;
{ This program demonstrates the MonthsBetween function }
Uses SysUtils,DateUtils;
Procedure Test(ANow,AThen : TDateTime);
begin
 Write('Number of months between ');
 Write(DateToStr(AThen),' and ',DateToStr(ANow));
 Writeln(' : ',MonthsBetween(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.