private void BtnEquals_Click(object sender, RoutedEventArgs e) { if (!Double.TryParse(input, out secondNum)) { SolutionTextBlock.Text = "Error"; } else { input = ""; } ans = Operations.PerformOperation(firstNum, secondNum, currentOperation); DisplayValue(firstNum + " " + content + " " + secondNum); SolutionTextBlock.Text = "Ans = " + ans; ResetValues(); }