private void Change_Name_Click(object sender, EventArgs e) { string value = ""; if (txtValue.Text == "") { MessageBox.Show("The value can't be nothing"); return; } try { value = txtValue.Text; ListViewItem item = listViewActivity.SelectedItems[0]; SomerenLogic.Activity_Service activity_Service = new Activity_Service(); activity_Service.UpdateName(value, int.Parse(item.Text)); } catch (ArgumentOutOfRangeException) { MessageBox.Show("Select an item"); return; } showPanel("Activity"); }