unit Unit1;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls;

type
  TMyRecord = record
    fLength: Cardinal;
    fCount: Cardinal;
    fReadOnly: Boolean;
  end;

  TForm1 = class(TForm)
    Button1: TButton;
    procedure Button1Click(Sender: TObject);
  private
    fMyRecord: TMyRecord;

  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}

procedure TForm1.Button1Click(Sender: TObject);
begin
  fMyRecord.fLength := 0;
  fMyRecord.fCount := 0;
  fMyRecord.fReadOnly := False;
end;

end.