public static void ClearLastSymbol(this DisplayNumber displayNumber)
{
if (displayNumber.HasComma)
{
if (!string.IsNullOrEmpty(displayNumber.FractionalPart))
{
displayNumber.FractionalPart = displayNumber.FractionalPart.Substring(0, displayNumber.FractionalPart.Length - 1);
}
else
{
displayNumber.HasComma = false;
}
}
else
{
var integerPartLength = displayNumber.IntegerPart.Length;
if (integerPartLength > 1)
{
displayNumber.IntegerPart = displayNumber.IntegerPart.Substring(0, integerPartLength - 1);
}
else
{
displayNumber.Reset();
}
}
}
private void ApplyNumber(char symbol)
{
if (_displayNumber.IsDefault())
{
_displayNumber.IntegerPart = string.Empty;
}
if (_isLastActionAnBinaryOperation || _isLastActionAnEquation)
{
_displayNumber.Reset();
_displayNumber.IntegerPart = string.Empty;
}
if (!_displayNumber.HasComma)
{
_displayNumber.IntegerPart += symbol;
}
else
{
_displayNumber.FractionalPart += symbol;
}
}