private void button1AddExpenses_Click(object sender, EventArgs e) { if (textBox1_add_exp.Text == "") { MessageBox.Show("Please, input how much money you want to add as expenses"); } else { int r = controllerObj.AddExpenses((int)comboBox1.SelectedValue, Convert.ToDouble(textBox1_add_exp.Text)); if (r > 0) { MessageBox.Show("Expenses added successfuly"); } else { MessageBox.Show("Error adding Expenses"); } } }