public MainForm()
{
InitializeComponent();
OperationHandlers = new Dictionary <String, BinaryOperation> {
};
foreach (var control in OperationPanel.Controls)
{
var button = control as Button;
var tag = button.Tag as String;
if (tag == "Number")
{
button.Click += OnNumberButtonClick;
}
if (tag == "BinaryOperation")
{
button.Click += OnOperatorButtonClick;
var operation = new BinaryOperation(button.Text);
OperationHandlers.Add(button.Text, operation);
}
button.Click += (object sender, EventArgs e) => UpdateLabels();
Input = new InputHandler();
}
}
private IOperation MultiplyOrDivision()
{
var operation = AnyOperation();
while (_position < _expression.Length)
{
if (CurrentOperator("*"))
{
operation = new BinaryOperation(operation, "*", AdditionOrSubtraction());
}
else if (CurrentOperator("/"))
{
var rightOperation = AdditionOrSubtraction();
if (rightOperation.Calculate().Equals(0))
{
throw new Exception(String.Format("Деление на 0 в операции {0}/{1}", operation, rightOperation));
}
operation = new BinaryOperation(operation, "/", rightOperation);
}
else
{
break;
}
}
return(operation);
}
public BackSpaceCommand(BinaryOperation op)
{
_Op = op;
_Op.PropertyChanged += (s, e) => {
if (CanExecuteChanged != null)
{
CanExecuteChanged(this, EventArgs.Empty);
}
};
}
private double Evaluate()
{
if (!(CurrentOperation is null))
{
right = Input.ToDouble();
if (left.HasValue && right.HasValue)
{
var result = CurrentOperation.Evaluate(left.Value, right.Value);
Input.init(result);
CurrentOperation = null;
left = result;
return(result);
}
else
{
return(0);
}
}
private IOperation AdditionOrSubtraction()
{
var operation = MultiplyOrDivision();
while (_position < _expression.Length)
{
if (CurrentOperator("+"))
{
operation = new BinaryOperation(operation, "+", AdditionOrSubtraction());
}
else if (CurrentOperator("-"))
{
operation = new BinaryOperation(operation, "-", AdditionOrSubtraction());
}
else
{
break;
}
}
return(operation);
}
private void OnOperatorButtonClick(object sender, EventArgs e)
{
var button = sender as Button;
if (CurrentOperation is null)
{
CurrentOperation = OperationHandlers[button.Text];
left = Input.ToDouble();
if (left is null)
{
return;
}
History = left.ToString() + CurrentOperation.ToString();
Input.init(left.GetValueOrDefault());
}
else
{
var result = Evaluate();
CurrentOperation = OperationHandlers[button.Text];
History = result.ToString() + CurrentOperation.ToString();
Input.init(result);
}
}
