[일반/컴포넌트] ListBox의 화면에 보여지는 최상위 Item 번호

unit Unit1;

interface

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

type
  TForm1 = class(TForm)
    ListBox1: TListBox;
    Button1: TButton;
    procedure Button1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation
{$R *.DFM}

procedure TForm1.Button1Click(Sender: TObject);
var
  FirstItem: Integer;
begin
  // 화면에 보여지는 최상위 Item 번호
  FirstItem := SendMessage(ListBox1.Handle, LB_GETTOPINDEX, 0, 0);
  ShowMessage(IntToStr(FirstItem));
end;

end.