public static IStrategy FindStrategy(char @operator)
{
IStrategy strategyToChange = null;
switch (@operator)
{
case '+':
strategyToChange = new AdditionStrategy();
break;
case '-':
strategyToChange = new SubtractionStrategy();
break;
case '*':
strategyToChange = new MultiplicationStrategy();
break;
case '/':
strategyToChange = new DivisionStrategy();
break;
default:
throw new ArgumentException($"Invalid operator {@operator} !");
}
return(strategyToChange);
}
public PrimitiveCalculator()
{
this.additionStrategy = new AdditionStrategy();
this.subtractionStrategy = new SubtractionStrategy();
this.multiplicationStrategy = new MultiplicationStrategy();
this.divisionStrategy = new DivisionStrategy();
this.isAddition = true;
}
static void Main() // 100/100 - Пример за DependencyInversion с ctor Injection!!!
{
PrimitiveCalculator calculator = new PrimitiveCalculator(new AdditionStrategy()); // default strategy!
string input;
while ((input = Console.ReadLine()) != "End")
{
string[] tokens = input.Split();
string command = tokens[0];
if (command == "mode")
{
char @operator = tokens[1][0];
ICalculationStrategy strategy = null;
switch (@operator)
{
case '+':
strategy = new AdditionStrategy();
break;
case '-':
strategy = new SubtractionStrategy();
break;
case '*':
strategy = new MultyplicationStrategy();
break;
case '/':
strategy = new DivisionStrategy();
break;
}
if (strategy == null)
{
throw new ArgumentException("Inavalid mode!");
}
calculator.ChangeStrategy(strategy);
}
else
{
int firstOperand = int.Parse(tokens[0]);
int secondOperand = int.Parse(tokens[1]);
int result = calculator.PerformCalculation(firstOperand, secondOperand);
Console.WriteLine(result);
}
}
}