procedure TMainForm.FormCreate(Sender: TObject);      
begin
  with TLoginForm.Create(Self) do          //現在是顯示登入畫面
  begin
    try
      if ShowModal<>mrOk then
        Application.Terminate;
    finally
      Free;
    end;
  end;
end;

procedure TLoginForm.Button1Click(Sender: TObject);     
var
  sUserName,sUserPWD,sSql:   String;
begin
  sUserName := Edit1.Text;
  sUserPWD  := Edit2.Text;      if sUserName = '' then
  begin
    Application.MessageBox('用戶名不能爲空，請重新檢查一下','注意',MB_OK);
    Edit1.SetFocus;
    Exit;
  end
  else if sUserPWD = '' then
  begin
    Application.MessageBox('密碼不能爲空，請重新檢查一下','注意',MB_OK);
    Edit2.SetFocus;
    Exit;
  end;      sSql := 'select * from UserPassword where UserName = "'   sUserName   '" and UserPWD = "'   sUserPWD   '"';      with ADOQuery1 do
  begin
    Close;
    SQL.Clear;
    SQL.Add(sSql);
    Open;
  end;      if ADOQuery1.RecordCount = 0 then
  begin
    Application.MessageBox('輸入的用戶名或密碼不對，請您重新檢查','注意',MB_OK);
    Edit1.SetFocus;
    Exit;
  end;      ADOQuery1.Close;      ModalResult := mrOk;
end;

引言: 不行耶!!做不出來!誰能夠救我!!我不懂???^^"