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Delphi DLL

DateTime - Add or Subtract Seconds

Demonstrates the AddSeconds method to add or subtract a number of seconds from a date/time.

Note: This example is only valid in Chilkat v9.5.0.65 or later.

Chilkat Delphi DLL Downloads

Delphi DLL
uses
    Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
    Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls, CkDateTime;

...

procedure TForm1.Button1Click(Sender: TObject);
var
dateTime: HCkDateTime;

begin
dateTime := CkDateTime_Create();

CkDateTime_SetFromCurrentSystemTime(dateTime);

Memo1.Lines.Add('Current time: ' + CkDateTime__getAsTimestamp(dateTime,False));

CkDateTime_AddSeconds(dateTime,1);
Memo1.Lines.Add('Current time + 1 second: ' + CkDateTime__getAsTimestamp(dateTime,False));

CkDateTime_AddSeconds(dateTime,-2);
Memo1.Lines.Add('Current time - 1 second: ' + CkDateTime__getAsTimestamp(dateTime,False));

// Add 30 days (60 * 60 * 24 * 30)
CkDateTime_AddSeconds(dateTime,60 * 60 * 24 * 30);
Memo1.Lines.Add('Current time + 30 days: ' + CkDateTime__getAsTimestamp(dateTime,False));

// Sample output for test run on 2-Dec-2016: 

// 	Current time: 2016-12-02T12:59:13Z
// 	Current time + 1 second: 2016-12-02T12:59:14Z
// 	Current time - 1 second: 2016-12-02T12:59:12Z
// 	Current time + 30 days: 2017-01-01T12:59:12Z

CkDateTime_Dispose(dateTime);

end;