private void btnAdd_Click(object sender, EventArgs e) { try { string name = textBoxName.Text.Trim(); if (!author.verifyData(name)) { showMessage("Утга хоосон байна!"); } else if (author.existData(name)) { showMessage("Exist"); } else { using (command = new MySqlCommand("INSERT INTO `authors`(`name`) VALUES (@name)", con)) { command.Parameters.Add("@name", MySqlDbType.VarChar).Value = name; executeQuery(command, "Зохиолч амжилттай нэмэгдлээ."); BookMain main = new BookMain(); CategoryController category = new CategoryController(); category.comboBox(main.cbAuthor, "authors"); } } } catch (Exception ex) { showMessage("Author: " + ex.Message); } }