private void OnGo(object sender, EventArgs e) { try { CalculateOptimalConstant calculator = new CalculateOptimalConstant(MinConstant, MaxConstant, Step); calculator.UpdateObserverEvent += UpdateMessage; object obj = _comboBoxVariableToUse.SelectedItem; if (null != obj) { ComboBoxItem it = (ComboBoxItem)obj; calculator.GetValue = it.GetValueMethod; int i = calculator.Calculate(); _txtboxoptimalConstant.Text = i.ToString(); } } catch (Exception ex) { MessageBox.Show(ex.Message, "Failed to Calculate Constant"); } }