/**
* Result text containing whole calculation with result according to given state.
*/
private string GetResultText(CalculationState state, bool usingCurrentState = false)
{
var first = state.FirstNumber;
var second = state.SecondNumber;
var operationType = state.OperationType;
if (first == null || second == null || operationType == null)
{
if (usingCurrentState)
{
RestoreCalculationState();
}
return("0");
}
var operation = GetOperationText(state);
var result = GetResult((double)first, (double)second, (OperationTypes)operationType);
var resultOperationText = state.FirstNumber + " " + operation + " " + state.SecondNumber + " = " + result;
if (usingCurrentState)
{
SaveAndRestoreCalculationState();
}
return(resultOperationText);
}
private string GetOperationText(CalculationState state)
{
switch (state.OperationType)
{
case OperationTypes.ADD: return("+");
case OperationTypes.SUBTRACT: return("-");
case OperationTypes.MULTIPLY: return("*");
case OperationTypes.DIVIDE: return("/");
default: return(null);
}
}
private void RestoreCalculationState()
{
state = new CalculationState();
}
public CalculatorManager()
{
state = new CalculationState();
calculationsList = new List <CalculationState>();
}