// | + - |
public static string AddSeparator(string expression)
{
string symbol = NumberFormatInfo.CurrentInfo.CurrencyDecimalSeparator;
char separator = symbol[0];
string result = expression;
bool correctLast = false;
for (int i = expression.Length - 1; i >= 0; i--)
{
if (!correctLast)
{
if (Contains.ToNumbers(expression[expression.Length - 1]))
{
correctLast = true;
}
else if (Contains.ToMathOperators(
expression[expression.Length - 1]) ||
expression[expression.Length - 1] == '(')
{
result += "0" + separator;
break;
}
else
{
break;
}
}
if (correctLast)
{
if (Contains.ToSeparators(expression[i]))
{
break;
}
if (Contains.ToAllOperators(expression[i]))
{
result += separator;
break;
}
if (i == 0 && Contains.ToNumbers(expression[i]))
{
result += separator;
}
}
}
if (expression.Length == 0)
{
result = "0" + separator;
}
return(result);
}
// | + - |
public static int FindNearestOperator(string expression)
{
for (int i = expression.Length - 1; i >= 0; i--)
{
if (Contains.ToNumbers(expression[i]))
{
continue;
}
if (Contains.ToSeparators(expression[i]))
{
continue;
}
return(i);
}
return(-1);
}
// | + - |
public static bool IsCorrect(string expression)
{
if (expression.Length == 0)
{
return(false);
}
bool isCorrect = false;
bool isCorrectBracket = true;
bool isCorrectSeparators = true;
bool isCorrectOperators = true;
bool haveABracket = false;
for (int i = 0; i < expression.Length; i++)
{
if (expression[i] == '(' || expression[i] == ')')
{
haveABracket = true;
break;
}
}
if (haveABracket)
{
isCorrectBracket = IsCorrectBracket(expression);
}
for (int i = 0; i < expression.Length; i++)
{
if (Contains.ToSeparators(expression[i]) && i == 0)
{
isCorrectSeparators = false;
}
else if (Contains.ToSeparators(expression[i]) &&
!Contains.ToNumbers(expression[i - 1]))
{
isCorrectSeparators = false;
}
if (Contains.ToSeparators(expression[i]) &&
expression.Length - 1 == i)
{
isCorrectSeparators = false;
}
else if (Contains.ToSeparators(expression[i]) &&
!Contains.ToNumbers(expression[i + 1]))
{
isCorrectSeparators = false;
}
if (Contains.ToMathOperators(expression[i]) &&
expression[i] != '-' && i == 0)
{
isCorrectOperators = false;
}
else if (Contains.ToMathOperators(expression[i]) &&
expression[i] != '-' && !Contains.ToNumbers(
expression[i - 1]) && expression[i - 1] != ')')
{
isCorrectOperators = false;
}
if (Contains.ToMathOperators(expression[i]) &&
i == expression.Length - 1)
{
isCorrectOperators = false;
}
else if (Contains.ToMathOperators(expression[i]) &&
expression[i + 1] != '-' && !Contains.ToNumbers(
expression[i + 1]) && expression[i + 1] != '(')
{
isCorrectOperators = false;
}
if (i != 0 && i != expression.Length - 1 &&
Contains.ToMathOperators(expression[i - 1]) &&
Contains.ToMathOperators(expression[i]) &&
Contains.ToMathOperators(expression[i + 1]))
{
isCorrectOperators = false;
}
}
if (isCorrectBracket && isCorrectSeparators && isCorrectOperators)
{
isCorrect = true;
}
return(isCorrect);
}
// | + - |
public static string Selector(string expression, int index)
{
expression = Parse.RemoveSpace(expression);
if (!Parse.IsCorrect(expression))
{
throw new NotCorrectException("Выражение не корректно.");
}
if (!Contains.ToMathOperators(expression[index]))
{
throw new Exception("Переданный индекс не является " +
"математическим оператором.");
}
if (Contains.ToAllOperators(expression[index - 1]))
{
throw new Exception("Переданный индекс оператора нельзя посчитать.");
}
int firstIndex = 0;
int lastIndex = 0;
for (int i = index - 1; i >= 0; i--)
{
if (i == 0 && !Contains.ToBrackets(expression[i]))
{
firstIndex = i;
break;
}
else if (expression[i] == '-' && Contains.ToAllOperators(
expression[i - 1]))
{
continue;
}
else if (Contains.ToAllOperators(expression[i]) &&
!Contains.ToSeparators(expression[i]))
{
firstIndex = i + 1;
break;
}
}
for (int i = index + 1; i < expression.Length; i++)
{
if (i == expression.Length - 1)
{
lastIndex = i;
break;
}
else if (i - index + 1 == 0 && expression[i] == '-')
{
continue;
}
else if (Contains.ToAllOperators(expression[i + 1]) &&
!Contains.ToSeparators(expression[i + 1]))
{
lastIndex = i;
break;
}
}
int subStringSize = lastIndex + 1 - firstIndex;
string result = expression.Substring(firstIndex, subStringSize);
return(result);
}
