Ввод функции в Textbox
Здравствуйте, мне необходимо реализовать ввод функции через текстбокс.
Начала писать код:
и нашла код для распознавания самой функции
но проблема вот в чем
как я поняла это описывается отдельный класс
но как его переделать на язык си шарп и как связать эти два кусочка не понимаю
может кто то подскажет ??или порекомендует что то другое для ввода для ввода функции через текстбокс??
Здравствуйте, мне необходимо реализовать ввод функции через текстбокс.
Начала писать код:
Код:
private void Form1_Load(object sender, EventArgs e)
{
string input = (textBox1.Text); // строка которую нужно разобрать
Function f = new Function(input); // создаем функцию
double result;
return result = f.calculate(x);
}
Код:
public class Parser
{
public const char START_ARG = '(';
public const char END_ARG = ')';
public const char END_LINE = '\n';
class Cell
{
internal Cell(double value, char action)
{
Value = value;
Action = action;
}
internal double Value { get; set; }
internal char Action { get; set; }
}
public static double process(string data)
{
// Get rid of spaces and check parenthesis
string expression = preprocess(data);
int from = 0;
return loadAndCalculate(data, ref from, END_LINE);
}
static string preprocess(string data)
{
if (string.IsNullOrEmpty(data))
{
throw new ArgumentException("Loaded empty data");
}
int parentheses = 0;
StringBuilder result = new StringBuilder(data.Length);
for (int i = 0; i < data.Length; i++)
{
char ch = data[i];
switch (ch)
{
case ' ':
case '\t':
case '\n': continue;
case END_ARG: parentheses--;
break;
case START_ARG: parentheses++;
break;
}
result.Append(ch);
}
if (parentheses != 0)
{
throw new ArgumentException("Uneven parenthesis");
}
return result.ToString();
}
public static double loadAndCalculate(string data, ref int from, char to = END_LINE)
{
if (from >= data.Length || data[from] == to)
{
throw new ArgumentException("Loaded invalid data: " + data);
}
List<Cell> listToMerge = new List<Cell>(16);
StringBuilder item = new StringBuilder();
do
{ // Main processing cycle of the first part.
char ch = data[from++];
if (stillCollecting(item.ToString(), ch, to))
{ // The char still belongs to the previous operand.
item.Append(ch);
if (from < data.Length && data[from] != to)
{
continue;
}
}
// We are done getting the next token. The getValue() call below may
// recursively call loadAndCalculate(). This will happen if extracted
// item is a function or if the next item is starting with a START_ARG '('.
ParserFunction func = new ParserFunction(data, ref from, item.ToString(), ch);
double value = func.getValue(data, ref from);
char action = validAction(ch) ? ch
: updateAction(data, ref from, ch, to);
listToMerge.Add(new Cell(value, action));
item.Clear();
} while (from < data.Length && data[from] != to);
if (from < data.Length &&
(data[from] == END_ARG || data[from] == to))
{ // This happens when called recursively: move one char forward.
from++;
}
Cell baseCell = listToMerge[0];
int index = 1;
return merge(baseCell, ref index, listToMerge);
}
static bool stillCollecting(string item, char ch, char to)
{
// Stop collecting if either got END_ARG ')' or to char, e.g. ','.
char stopCollecting = (to == END_ARG || to == END_LINE) ?
END_ARG : to;
return (item.Length == 0 && (ch == '-' || ch == END_ARG)) ||
!(validAction(ch) || ch == START_ARG || ch == stopCollecting);
}
static bool validAction(char ch)
{
return ch == '*' || ch == '/' || ch == '+' || ch == '-' || ch == '^';
}
static char updateAction(string item, ref int from, char ch, char to)
{
if (from >= item.Length || item[from] == END_ARG || item[from] == to)
{
return END_ARG;
}
int index = from;
char res = ch;
while (!validAction(res) && index < item.Length)
{ // Look for the next character in string until a valid action is found.
res = item[index++];
}
from = validAction(res) ? index
: index > from ? index - 1
: from;
return res;
}
// From outside this function is called with mergeOneOnly = false.
// It also calls itself recursively with mergeOneOnly = true, meaning
// that it will return after only one merge.
static double merge(Cell current, ref int index, List<Cell> listToMerge,
bool mergeOneOnly = false)
{
while (index < listToMerge.Count)
{
Cell next = listToMerge[index++];
while (!canMergeCells(current, next))
{ // If we cannot merge cells yet, go to the next cell and merge
// next cells first. E.g. if we have 1+2*3, we first merge next
// cells, i.e. 2*3, getting 6, and then we can merge 1+6.
merge(next, ref index, listToMerge, true /* mergeOneOnly */);
}
mergeCells(current, next);
if (mergeOneOnly)
{
return current.Value;
}
}
return current.Value;
}
static void mergeCells(Cell leftCell, Cell rightCell)
{
switch (leftCell.Action)
{
case '^': leftCell.Value = Math.Pow(leftCell.Value, rightCell.Value);
break;
case '*': leftCell.Value *= rightCell.Value;
break;
case '/':
if (rightCell.Value == 0)
{
throw new ArgumentException("Division by zero");
}
leftCell.Value /= rightCell.Value;
break;
case '+': leftCell.Value += rightCell.Value;
break;
case '-': leftCell.Value -= rightCell.Value;
break;
}
leftCell.Action = rightCell.Action;
}
static bool canMergeCells(Cell leftCell, Cell rightCell)
{
return getPriority(leftCell.Action) >= getPriority(rightCell.Action);
}
static int getPriority(char action)
{
switch (action) {
case '^': return 4;
case '*':
case '/': return 3;
case '+':
case '-': return 2;
}
return 0;
}
}
public class ParserFunction
{
public ParserFunction()
{
m_impl = this;
}
// A "virtual" Constructor
internal ParserFunction(string data, ref int from, string item, char ch)
{
if (item.Length == 0 && ch == Parser.START_ARG)
{
// There is no function, just an expression in parentheses
m_impl = s_idFunction;
return;
}
if (m_functions.TryGetValue(item, out m_impl))
{
// Function exists and is registered (e.g. pi, exp, etc.)
return;
}
// Function not found, will try to parse this as a number.
s_strtodFunction.Item = item;
m_impl = s_strtodFunction;
}
public static void addFunction(string name, ParserFunction function)
{
m_functions[name] = function;
}
public double getValue(string data, ref int from)
{
return m_impl.evaluate(data, ref from);
}
protected virtual double evaluate(string data, ref int from)
{
// The real implementation will be in the derived classes.
return 0;
}
private ParserFunction m_impl;
private static Dictionary<string, ParserFunction> m_functions = new Dictionary<string, ParserFunction>();
private static StrtodFunction s_strtodFunction = new StrtodFunction();
private static IdentityFunction s_idFunction = new IdentityFunction();
}
class StrtodFunction : ParserFunction
{
protected override double evaluate(string data, ref int from)
{
double num;
if (!Double.TryParse(Item, out num)) {
throw new ArgumentException("Could not parse token [" + Item + "]");
}
return num;
}
public string Item { private get; set; }
}
class IdentityFunction : ParserFunction
{
protected override double evaluate(string data, ref int from)
{
return Parser.loadAndCalculate(data, ref from, Parser.END_ARG);
}
}
class PiFunction : ParserFunction
{
protected override double evaluate(string data, ref int from)
{
return 3.141592653589793;
}
}
class ExpFunction : ParserFunction
{
protected override double evaluate(string data, ref int from)
{
double arg = Parser.loadAndCalculate(data, ref from, Parser.END_ARG);
return Math.Exp(arg);
}
}
class PowFunction : ParserFunction
{
protected override double evaluate(string data, ref int from)
{
double arg1 = Parser.loadAndCalculate(data, ref from, ',');
double arg2 = Parser.loadAndCalculate(data, ref from, Parser.END_ARG);
return Math.Pow(arg1, arg2);
}
}
class SinFunction : ParserFunction
{
protected override double evaluate(string data, ref int from)
{
double arg = Parser.loadAndCalculate(data, ref from, Parser.END_ARG);
return Math.Sin(arg);
}
}
class SqrtFunction : ParserFunction
{
protected override double evaluate(string data, ref int from)
{
double arg = Parser.loadAndCalculate(data, ref from, Parser.END_ARG);
return Math.Sqrt(arg);
}
}
class AbsFunction : ParserFunction
{
protected override double evaluate(string data, ref int from)
{
double arg = Parser.loadAndCalculate(data, ref from, Parser.END_ARG);
return Math.Abs(arg);
}
}как я поняла это описывается отдельный класс
но как его переделать на язык си шарп и как связать эти два кусочка не понимаю
может кто то подскажет ??или порекомендует что то другое для ввода для ввода функции через текстбокс??