public void OperationButtonPress(string operation) { newDisplayRequired = true; try { if (FirstOperand == String.Empty || LastOperation == "=") { FirstOperand = Display; LastOperation = operation; Expression = calculation.ToHalfExpressionString(operation); } else { SecondOperand = Display; Operation = LastOperation; calculation.CalculateResult(); Expression = calculation.ToFullExpressionString(); History.Add(String.Format("{0} {1}", Expression, Result)); LastOperation = operation; Display = Result; FirstOperand = Display; } } catch (Exception) { Display = Result == String.Empty ? "Error" : Result; } }
public static string ToHalfExpressionString(this CalculationModel model) { return(model.ToHalfExpressionString(model.Operation)); }