private void btnEquals_Click(object sender, RoutedEventArgs e)
{
double newNumber;
if (double.TryParse(LblResult.Content.ToString(), out newNumber))
{
switch (_selectedOperator)
{
case Operation.Add:
_result = _calculations.Add(_lastNumber, newNumber);
break;
case Operation.Subtract:
_result = _calculations.Subtract(_lastNumber, newNumber);
break;
case Operation.Multiply:
_result = _calculations.Multiply(_lastNumber, newNumber);
break;
case Operation.Divide:
_result = _calculations.Divide(_lastNumber, newNumber);
break;
}
LblResult.Content = _result;
}
}