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{

 The timeSetEvent function starts a specified timer event.

 The multimedia timer runs in its own thread. After the event is activated,

 it calls the specified callback function or sets or pulses the spe

 cified event object.

 MMRESULT timeSetEvent(

 UINT           uDelay,

 UINT           uResolution,

 LPTIMECALLBACK lpTimeProc,

 DWORD_PTR      dwUser,

 UINT           fuEvent

 );

 uDelay:

  Event delay, in milliseconds

 uResolution:

  Resolution of the timer event, in milliseconds.

  A resolution of 0 indicates periodic events should occur with the

  greatest possible accuracy.

  You should use the use the maximum value appropriate to reduce system overhead.

 fuEvent:

  TIME_ONESHOT Event occurs once, after uDelay milliseconds.

  TIME_PERIODIC Event occurs every uDelay milliseconds.

}

uses

 MMSystem;

var

 mmResult: Integer;

// callback function

procedure TimeCallBack(TimerID, Msg: Uint; dwUser, dw1, dw2: DWORD); pascal;

begin

 // Do something here. This procedure will be executed each 10 ms

 Form1.Label1.Caption := Form1.Label1.Caption + '%';

end;

// Set a new timer with a delay of 10 ms

procedure TForm1.Button1Click(Sender: TObject);

begin

 mmResult := TimeSetEvent(10, 0, @TimeCallBack, 0, TIME_PERIODIC);

end;

// Cancel the timer event.

procedure TForm1.FormDestroy(Sender: TObject);

begin

 TimeKillEvent(mmResult);

end;