private void BackgroundWorker_DoWork(object sender, DoWorkEventArgs e)
        {
            try
            {
                using (DBWokrSql db = new DBWokrSql(Connection))
                {
                    var levels_ = (Dictionary <int, string>)db.GetLevels();
                    var topics_ = (Dictionary <int, string>)db.GetTopics();

                    var qq = new Dictionary <QuestionInfo, IEnumerable <AnswerInfo> >();

                    foreach (var item in db.GetIDQuestions(0, 0))
                    {
                        var question_ = db.GetQuestion(item);

                        var answers_ = db.GetAnswers(item);

                        qq.Add(question_, answers_);
                    }

                    e.Cancel = false;
                    e.Result = new { lev = levels_, topi = topics_, q = qq };
                }
            }
            catch (Exception ex)
            {
                e.Cancel = false;
                e.Result = "Не має зв`язку з базою: " + ex.Message;
            }
        }
        void SearchQuestion()
        {
            try
            {
                currentQuestions = new Dictionary <QuestionInfo, IEnumerable <AnswerInfo> >();
                var a = (comboBox1.SelectedItem as Data) == null ? 0 : (comboBox1.SelectedItem as Data).ID;
                var b = (comboBox.SelectedItem as Data) == null ? 0 : (comboBox.SelectedItem as Data).ID;
                currentQuestions.Clear();
                using (DBWokrSql db = new DBWokrSql(Connection))
                {
                    foreach (var item in db.GetIDQuestions(a, b))
                    {
                        var question_ = db.GetQuestion(item);

                        var answers_ = db.GetAnswers(item);

                        currentQuestions.Add(question_, answers_);
                    }
                }

                labelSearch.Content = "Знайдено :" + currentQuestions.Keys.Count;

                if (currentQuestions.Keys.Count == 0)
                {
                    frameView.Navigate(new UserControlNewQuestion(Connection)); return;
                }

                currentQuest = 0;

                var Cquest = currentQuestions.Keys.ElementAt(currentQuest);

                frameView.Navigate(new UserControlNewQuestion(Connection, currentQuest, currentQuestions.Keys.Count, Cquest, currentQuestions[Cquest]));
            }
            catch (Exception ex)
            {
                MessageBox.Show("Search Question " + ex.Message);
            }
        }