Инкрементальный поиск в ListBox 2

unit LbxSrch;

interface

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

type
  TFrmLbxSrch = class(TForm)
    Edit1: TEdit;
    Edit2: TEdit;
    ListBox1: TListBox;
    Label1: TLabel;
    procedure FormKeyPress(Sender: TObject; var Key: Char);
    procedure ListBox1Enter(Sender: TObject);
  private { Private declarations }
    FPrefix: array[0..255] of char;
  public
    { Public declarations }
  end;

var
  FrmLbxSrch: TFrmLbxSrch;

implementation

{$R *.DFM}

procedure TFrmLbxSrch.FormKeyPress(Sender: TObject; var Key: Char);
{ Помните о том, что свойство KeyPreview должно быть установлено в True }
var
  curKey: array[0..1] of char;
  ndx: integer;
begin
  if ActiveControl = ListBox1 then
  begin
    if key = #8 {Backspace (клавиша возврата)} then
    begin
      if FPrefix[0] <> #0 then
      begin
        FPrefix[StrLen(FPrefix) - 1] := #0;
      end
    end
    else
    begin
      curKey[0] := Key;
      curKey[1] := #0;
      StrCat(FPrefix, curKey);
      ndx := SendMessage(ListBox1.Handle, LB_FINDSTRING,
        -1, longint(@FPrefix));
      if ndx <> LB_ERR then
        ListBox1.ItemIndex := ndx;
    end;

    Label1.Caption := StrPas(FPrefix);
    Key := #0;
  end;
end;

procedure TFrmLbxSrch.ListBox1Enter(Sender: TObject);
begin
  FPrefix[0] := #0;
  Label1.Caption := StrPas(FPrefix);
end;

end.