private void returnBookButton_Click(object sender, EventArgs e) { if (userShowcomboBox.SelectedItem == null) { MessageBox.Show("Izberite Ĩlana."); } else { databaseController dbc = new databaseController(); string selectedUser = userShowcomboBox.SelectedItem.ToString();//exception needs to be handled selectedUser = selectedUser.Trim(); string[] UserID = selectedUser.Split('|'); int id_u = Convert.ToInt32(UserID[0].Trim()); string name = UserID[1].Trim();//title string surname = UserID[2].Trim(); string tel = UserID[3].Trim(); string address = UserID[3].Trim(); string location_name = UserID[3].Trim(); string location_postalcode = UserID[3].Trim(); Locations lid = new Locations(0, location_name, ""); dbc.idLocations(lid); int location_id = 0; foreach (int k in dbc.idLocations(lid)) { location_id = k; } Users uid = new Users(0, name, surname, "", "", "", "", 0); dbc.idUsers(uid); int user_id = 0; foreach (int k in dbc.idUsers(uid)) { user_id = k; } if (userUnLendedBookslistBox.SelectedItem == null) { MessageBox.Show("Izberite knjigo."); } else { string selectedBook = userLendedBookslistBox.SelectedItem.ToString();//exception needs to be handled selectedBook = selectedBook.Trim(); string[] BookID = selectedBook.Split('|'); int id_b = Convert.ToInt32(BookID[0].Trim()); selectedBook = BookID[1].Trim();//title string author_name = BookID[2].Trim(); string author_surname = BookID[3].Trim(); int lost = Convert.ToInt32(BookID[4].Trim()); string year = BookID[5].Trim(); string location_name_book = BookID[6].Trim(); string publisher_name = BookID[7].Trim(); string genre_genretype = BookID[8].Trim(); int id_g = 0; Authors aid = new Authors(0, author_name, author_surname); dbc.idAuthors(aid); int author_id = 0; foreach (int k in dbc.idAuthors(aid)) { author_id = k; } Locations lid_book = new Locations(0, location_name, ""); dbc.idLocations(lid); int location_id_book = 0; foreach (int k in dbc.idLocations(lid)) { location_id = k; } Publishers pid = new Publishers(0, publisher_name); dbc.idPublishers(pid); int publisher_id = 0; foreach (int k in dbc.idPublishers(pid)) { publisher_id = k; } Genres gid = new Genres(0, genre_genretype); dbc.idGenres(gid); int genre_id = 0; foreach (int k in dbc.idGenres(gid)) { genre_id = k; } Rents rid = new Rents(0, 0, "", id_b, user_id); dbc.idRents(rid); int rent_id = 0; foreach (int k in dbc.idRents(rid)) { rent_id = k; } string rent_date = Convert.ToString(DateTime.Now); int rent_state = 0; Rents rentss = new Rents(rent_id, rent_state, rent_date, id_b, id_u); dbc.UpdateRentsUnLend(rentss); userUnLendedBookslistBox.Items.Clear(); userLendedBookslistBox.Items.Clear(); OutputBooksOnRents_UnLended(); } } }