The increasing time function in Delphi

Incyear, Incmonth, Incweek, Incday, Inchour, Incminute, Incsecond, Incmillisecond-Increase

DateUtils.IncYear();
DateUtils.IncMonth();
DateUtils.IncWeek();
DateUtils.IncDay();
DateUtils.IncHour();
DateUtils.IncMinute();
DateUtils.IncSecond();
DateUtils.IncMilliSecond();

Unit Unit1;

Interface

Uses
Windows, Messages, sysutils, variants, Classes, Graphics, Controls, Forms,
Dialogs, Stdctrls;

Type
TForm1 = Class (Tform)
Procedure Formcreate (Sender:tobject);
End

Var
Form1:tform1;

Implementation

{$R *.DFM}

Uses dateutils;

Procedure Tform1.formcreate (Sender:tobject);
Var
T1,t2:tdatetime;
I:int64;
d:double;
Begin
T1: = Strtodatetime (' 2011-1-1 1:1:1 ');

T2: = incyear (t1);
ShowMessage (Datetimetostr (T2)); 2012-1-1 1:01:01

T2: = Incyear (t1, 3);
ShowMessage (Datetimetostr (T2)); 2014-1-1 1:01:01

T2: = Incmonth (t1);
ShowMessage (Datetimetostr (T2)); 2011-2-1 1:01:01

T2: = Incweek (t1);
ShowMessage (Datetimetostr (T2)); 2011-1-8 1:01:01

T2: = Incday (t1);
ShowMessage (Datetimetostr (T2)); 2011-1-2 1:01:01

T2: = Inchour (t1);
ShowMessage (Datetimetostr (T2)); 2011-1-1 2:01:01

T2: = Incminute (t1);
ShowMessage (Datetimetostr (T2)); 2011-1-1 1:02:01

T2: = Incsecond (t1);
ShowMessage (Datetimetostr (T2)); 2011-1-1 1:01:02

T2: = Incmillisecond (t1);
ShowMessage (FormatDateTime (' yyyy-m-d h:n:s:zzz ', T2)); 2011-1-1 1:01:01:001
End

End.