private IList<ClientTable> RetriveData(Engine.SearchClientEngine search) { if(search_all_radiobutton.IsChecked == true) { return search.FindAllData().ToList(); } else if(search_using_ID_radiobutton.IsChecked == true) { if(id_textBox.Text == null) { System.Windows.MessageBox.Show("You have enter anything"); } else { try { int id = Int32.Parse(id_textBox.Text); return search.FindClientWithID(id).ToList(); } catch (FormatException e) { System.Console.WriteLine(e.Message); } } } else if(search_using_Names_radiobutton.IsChecked == true) { if (forename_textbox.Text == null && surname_textBox.Text == null) { System.Windows.MessageBox.Show("You have not entered names"); } else { return search.FindClientsWithNames(forename_textbox.Text, surname_textBox.Text).ToList(); } } else if(search_Clients_Using_Location_radiobutton.IsChecked == true) { if(city_textBox.Text == null && country_textBox.Text == null) { System.Windows.MessageBox.Show("you haven't entered antthing"); } else { return search.FindClientLivingIn(city_textBox.Text, country_textBox.Text).ToList(); } } return null; }