How to handle system time change

If you need to react when system date time has changed you can handle the WM_TimeChange Windows message.
Here's a sample code:

~~~~~~~~~~~~~~~~~~~~~~~~~
type
   TForm1 = class(TForm)
   private
     procedure WMTimeChange(var Msg: TMessage) ; message WM_TIMECHANGE;
   end;

var
   Form1: TForm1;

implementation
{$R *.DFM}

procedure TForm1.WMTimeChange(var Msg: TMessage) ;
begin
   inherited;
   ShowMessage('Date/Time has changed!') ;
end;
~~~~~~~~~~~~~~~~~~~~~~~~~

Note: the "Handling Windows Messages the Delphi way" article has more info on Windows message handling from Delphi code.

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