unit U_selectBK;

interface

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

type
  TF_selectBK = class(TForm)
    CheckListBox1: TCheckListBox;
    BitBtn1: TBitBtn;
    BitBtn2: TBitBtn;
    Label1: TLabel;
    MaskEdit1: TMaskEdit;
    MaskEdit2: TMaskEdit;
    Label2: TLabel;
    procedure FormDestroy(Sender: TObject);
    procedure FormClose(Sender: TObject; var Action: TCloseAction);
    procedure BitBtn1Click(Sender: TObject);
    procedure MaskEdit1Change(Sender: TObject);
  private
    { Private declarations }
    flag:Boolean;
  public
    { Public declarations }
  end;

var
  F_selectBK: TF_selectBK;

implementation

{$R *.DFM}

procedure TF_selectBK.FormDestroy(Sender: TObject);
begin
  F_selectBK:=nil;
end;

procedure TF_selectBK.FormClose(Sender: TObject; var Action: TCloseAction);
begin
  if flag then
  if (Length(Trim(MaskEdit1.Text))+Length(Trim(Maskedit2.text))<>20)or
    (MaskEdit1.Text>Maskedit2.text) then
    Begin
      Application.MessageBox('