unit DL;

interface

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

type
  TDLForm = class(TForm)
    Label1: TLabel;
    Label2: TLabel;
    EditCode: TEdit;
    Label3: TLabel;
    EditPWD: TEdit;
    BtOk: TBitBtn;
    BtCancel: TBitBtn;
    Table1: TTable;
    procedure BtOkClick(Sender: TObject);
    procedure BtCancelClick(Sender: TObject);
    procedure FormClose(Sender: TObject; var Action: TCloseAction);
    procedure FormShow(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  DLForm: TDLForm;
  M_AppTerMinate:boolean;
implementation

{$R *.dfm}

procedure TDLForm.BtOkClick(Sender: TObject);
begin
 Table1.Open;
 if Table1.FindKey([Trim(EditCode.Text)])=False then
 begin
  showmessage('error no this UserId ! again');
  EditCode.Text:='';
  EditCode.SetFocus;
  Exit;
  end;
 if Table1.FieldValues['password']<>Trim(EditPWD.Text) then
 begin
  showmessage('error password ! again');
  EditPWD.Text:='';
  EditPWD.SetFocus;
  Exit;
  end;
  Table1.Close;
  M_AppTerminate:=False;
  DLForm.Close;
end;

procedure TDLForm.BtCancelClick(Sender: TObject);
begin
 Application.Terminate;
end;

procedure TDLForm.FormClose(Sender: TObject; var Action: TCloseAction);
begin
  if M_AppTerminate=true then
  Application.Terminate;
end;

procedure TDLForm.FormShow(Sender: TObject);
begin
 M_AppTerminate:=true;
end;

end.