private void btnCalculate_Click(object sender, EventArgs e)
{
try
{
var input = txtMessage.Text;
var equation = EquationHelper.RemoveWhitespace(input);
if (EquationValidator.IsEquationValid(equation))
{
var result = EquationTreeGenerator.Calculation(equation).getValue();
txtMessage.Text = result.ToString();
lblMessage.Text = "Enter another equation";
}
else
{
lblMessage.Text = "Invalid Equation! Please try again";
}
}
catch (InvalidEquationException ex)
{
lblMessage.Text = ex.Message;
}
}
public static bool IsEquationValid(string _input)
{
if (string.IsNullOrEmpty(_input))
{
return(false);
}
var hasInvalidCharacter = _input.Any(_character =>
!(EquationHelper.IsCharacterNumber(_character) ||
EquationHelper.IsCharacterOperator(_character) ||
(EquationHelper.IsBracketsValid(_input, EquationHelper.IsCharacterBracket(_character)) && EquationHelper.IsCharacterBracket(_character))));
if (hasInvalidCharacter)
{
return(false);
}
if (EquationHelper.IsNumberMultipleDecimal(_input))
{
return(false);
}
if (EquationHelper.IsLastCharacterAOperator(_input))
{
return(false);
}
if (EquationHelper.IsOperatorDuplicated(_input))
{
return(false);
}
return(true);
}
public double CalculateEquation(string equation)
{
var numberCharacterBuilder = new StringBuilder();
var numbers = new List <int>();
var operators = new List <char>();
double result = 0;
int counter = 0;
var Operation = new OperatorFactory();
calcManager = new CalculationManager();
var updatedPreviousResult = 0;
var updatedCurrentValue = 0;
foreach (var character in equation)
{
if (EquationHelper.IsCharacterNumber(character))
{
numberCharacterBuilder.Append(character);
}
else
{
if (NumbersListValidator.IsListEmpty(numbers))
{
updatedPreviousResult = UpdateCalcManagerPrevious(numbers, numberCharacterBuilder.ToString());
numberCharacterBuilder.Clear();
}
else
{
updatedCurrentValue = UpdateCalcManagerCurrent(numbers, numberCharacterBuilder.ToString());
numberCharacterBuilder.Clear();
var NextOperation = Operation.GetOperator(operators[counter - 1]);
result = NextOperation.DoMaths(updatedPreviousResult, updatedCurrentValue);
updatedPreviousResult = UpdateCalcManagerPrevious(numbers, result.ToString());
}
counter++;
operators.Add(character);
}
}
updatedCurrentValue = UpdateCalcManagerCurrent(numbers, numberCharacterBuilder.ToString());
var LastOperation = Operation.GetOperator(operators[operators.Count() - 1]);
result = LastOperation.DoMaths(updatedPreviousResult, updatedCurrentValue);
return(result);
}
public static IEquationNode Calculation(string equation)
{
if (EquationHelper.IsWholeEquationWithinBrackets(equation) && EquationHelper.EquationContainsAnUnbracketedOperator(equation))
{
return(Calculation(equation.Substring(1, equation.Length - 2)));
}
if (EquationHelper.IsStringNumber(equation))
{
return(new Number(equation));
}
foreach (var op in EquationHelper.orderedOperators)
{
var bracketCounter = 0;
for (int i = 0; i < equation.Length; i++)
{
if (equation[i] == '(')
{
bracketCounter++;
}
else if (equation[i] == ')')
{
bracketCounter--;
}
if (equation[i] == op && bracketCounter == 0)
{
return(new EquationNode(
equation.Substring(0, i),
equation.Substring(i + 1),
Operation.GetOperator(equation[i])));
}
}
}
throw new InvalidEquationException("Equation is Invalid!");
}
