// | + - |
public static string AddOpenBracket(string expression)
{
int openBracketLeft = CountOpenBrackets(expression);
char lastSymbol = GetLastSymbol(expression);
if (lastSymbol == ' ')
{
return(expression + '(');
}
else if (lastSymbol == '.' || lastSymbol == ',')
{
return(expression);
}
else if (!Contains.ToNumbers(lastSymbol) &&
!Contains.ToAllOperators(lastSymbol))
{
return(expression);
}
else if (lastSymbol == ')' || Contains.ToNumbers(lastSymbol))
{
return(expression + '×' + '(');
}
else if (Contains.ToAllOperators(lastSymbol))
{
return(expression + '(');
}
return(expression);
}
// | + - |
public static string AddSymbol(string expression, char symbol)
{
string result = expression;
char lastSymbol = GetLastSymbol(expression);
if (lastSymbol == ')' && Contains.ToNumbers(symbol))
{
result = expression + '×' + symbol;
}
else if (lastSymbol == ')' && Contains.ToMathOperators(symbol))
{
result = expression + symbol;
}
else if (Contains.ToNumbers(lastSymbol) ||
Contains.ToNumbers(symbol))
{
result = expression + symbol;
}
else if (Contains.ToMathOperators(lastSymbol) &&
Contains.ToMathOperators(symbol) &&
(Contains.ToNumbers(expression[expression.Length - 2]) ||
expression[expression.Length - 2] == ')'))
{
result = ReplaceOperator(expression, expression.Length - 1,
symbol);
}
result = result.Replace(" ", "");
return(result);
}
// | + - |
public static string InvertNumber(string expression)
{
string result;
int operatorIndex = FindNearestOperator(expression);
if (operatorIndex == -1 || expression.Length == 0)
{
result = '-' + expression;
}
else if (expression[operatorIndex] == '+')
{
result = ReplaceOperator(expression, operatorIndex, '-');
}
else if (expression[operatorIndex] == '(' &&
expression.Length - 1 > operatorIndex &&
Contains.ToNumbers(expression[operatorIndex + 1]))
{
result = expression.Insert(operatorIndex + 1, "-");
}
else if (operatorIndex == 0 && expression[operatorIndex] == '(')
{
result = expression + '-';
}
else if (operatorIndex == 0)
{
result = ReplaceOperator(expression, operatorIndex, ' ');
}
else if (expression[operatorIndex - 1] == '(' &&
expression[operatorIndex] == '-')
{
result = ReplaceOperator(expression, operatorIndex, ' ');
}
else if (expression[operatorIndex - 1] == ')' &&
expression[operatorIndex] == '-')
{
result = ReplaceOperator(expression, operatorIndex, '+');
}
else if (Contains.ToAllOperators(expression[operatorIndex - 1]) &&
expression[operatorIndex] == '-')
{
result = ReplaceOperator(expression, operatorIndex, ' ');
}
else if (Contains.ToNumbers(expression[operatorIndex - 1]) &&
expression[operatorIndex] == '-')
{
result = ReplaceOperator(expression, operatorIndex, '+');
}
else
{
result = expression.Insert(operatorIndex + 1, "-");
}
result = result.Replace(" ", "");
return(result);
}
// | + - |
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 string AddBracket(string expression)
{
int openBracketLeft = CountOpenBrackets(expression);
char lastSymbol = GetLastSymbol(expression);
if (openBracketLeft == 0)
{
return(AddOpenBracket(expression));
}
else if (lastSymbol == ')' || Contains.ToNumbers(lastSymbol))
{
return(AddCloseBracket(expression));
}
else
{
return(AddOpenBracket(expression));
}
}
// | + - |
public static int PriorityOfOperations(string expression)
{
expression = Parse.RemoveSpace(expression);
if (!Parse.IsCorrect(expression))
{
throw new NotCorrectException("Выражение не корректно.");
}
string[] priorityOperators = { "×÷*/", "+-" };
bool openBracket = false;
int firstIndex = 1;
int lastIndex = expression.Length - 1;
for (int i = 0; i < expression.Length; i++)
{
if (expression[i] == '(')
{
openBracket = true;
firstIndex = i;
}
else if (expression[i] == ')' && openBracket)
{
lastIndex = i;
break;
}
}
foreach (string operators in priorityOperators)
{
for (int i = firstIndex; i < lastIndex + 1; i++)
{
if (operators.Contains(expression[i]) &&
Contains.ToNumbers(expression[i - 1]))
{
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);
}
