CompareDateTime

Compare 2 dates, taking into account the time of day

Declaration

Source position: dateutil.inc line 361

  function CompareDateTime(const A: TDateTime; const B: TDateTime)
                           : TValueRelationship;

Description

CompareDateTime compares two timestamps A and B and returns the following results:

< 0

if A is earlier in date/time than B.

0

if A and B are the same date/time .

> 0

if A is later in date/time than B.

See also

Name	Description
CompareDate	Compare 2 dates, disregarding the time of day
CompareTime	Compares two times of the day, disregarding the date part.
SameDate	Check whether two TDateTime values have the same date part.
SameDateTime	Check whether two TDateTime values have the same date and time parts.
SameTime	Check whether two TDateTime values have the same time part.

Example

Program Example98;
{ This program demonstrates the CompareDateTime function }
Uses SysUtils,DateUtils;
Const
  Fmt = 'dddd dd mmmm yyyy hh:nn:ss.zzz';
Procedure Test(D1,D2 : TDateTime);
Var
  Cmp : Integer;
begin
  Write(FormatDateTime(Fmt,D1),' is ');
  Cmp:=CompareDateTime(D1,D2);
  If Cmp<0 then
    write('earlier than ')
  else if Cmp>0 then
    Write('later than ')
  else
    Write('equal to ');
  Writeln(FormatDateTime(Fmt,D2));
end;
Var
  D,N : TDateTime;
Begin
  D:=Today;
  N:=Now;
  Test(D,D);
  Test(N,N);
  Test(D+1,D);
  Test(D-1,D);
  Test(D+OneSecond,D);
  Test(D-OneSecond,D);
  Test(N+OneSecond,N);
  Test(N-OneSecond,N);
End.