/// <summary>
/// Method for calculating the math expretion, returns the result
/// </summary>
/// <param name="operation"></param>
private string calculate_operation(Calc_operation operation)
{
double left = 0;
double right = 0;
// validating the inputted data
if (string.IsNullOrEmpty(operation.left_side_operation) || !double.TryParse(operation.left_side_operation, out left))
{
throw new InvalidOperationException($"No number located on the left side of the equation. {operation.left_side_operation}");
}
if (string.IsNullOrEmpty(operation.right_side_operation) || !double.TryParse(operation.right_side_operation, out right))
{
throw new InvalidOperationException($"No number located on the left side of the equation. {operation.right_side_operation}");
}
try
{
switch (operation.operators)
{
case Operators.add:
return((left + right).ToString());
break;
case Operators.substract:
return((left - right).ToString());
break;
case Operators.multiply:
return((left * right).ToString());
break;
case Operators.divide:
return((left / right).ToString());
break;
case Operators.percentage:
return((left % right).ToString());
default:
throw new InvalidOperationException($"Invalid math operation. {operation.operators}");
break;
}
}catch (Exception x)
{
throw new InvalidOperationException($"Invalid calculation. {operation.left_side_operation} " +
$"{operation.operators} {operation.right_side_operation}");
}
// returning empty string
return(string.Empty);
}
/// <summary>
/// Method to calculate the result and to convert it into string
/// </summary>
/// <returns></returns>
private string resOperation()
{
try
{
// take the user input
var user = this.UserInput.Text;
// removing the spaces
user = user.Replace(" ", "");
var operation = new Calc_operation();
// setting a boolean for the left side of the operation to true
var left_side = true;
// looping trough each character from the left
for (int i = 0; i < user.Length; ++i)
{
// string containing the valid numeric values
var strNumbers = "0123456789.";
// string containing the valid math operations
var strMathOperations = "+-/*%";
// validating the input
if (strNumbers.Any(num => user[i] == num))
{
if (left_side)
{
operation.left_side_operation = AddPartNum(operation.left_side_operation, user[i]);
}
else
{
operation.right_side_operation = AddPartNum(operation.right_side_operation, user[i]);
}
}
else if (strMathOperations.Any(num => user[i] == num))
{
if (!left_side)
{
var typeOperation = getTypeOperation(user[i]);
if (operation.right_side_operation.Length == 0)
{
if (typeOperation != Operators.substract)
{
throw new InvalidOperationException($"Invalid operator specified");
}
operation.right_side_operation += user[i];
}
else
{
operation.left_side_operation = calculate_operation(operation);
operation.operators = typeOperation;
operation.right_side_operation = string.Empty;
}
}
else
{
var typeOperation = getTypeOperation(user[i]);
if (operation.left_side_operation.Length == 0)
{
if (typeOperation != Operators.substract)
{
throw new InvalidOperationException($"Invalid operator specified");
}
operation.left_side_operation += user[i];
}
else
{
operation.operators = typeOperation;
left_side = false;
}
}
}
}
// returning calculate_operation method
return(calculate_operation(operation));
throw new ArgumentException("Invalid argument");
}
catch (Exception x)
{
return($"Invalid input. \n{x.Message}");
}
}