//Hier werden vorbereitende Arbeiten durchgeführt.
protected virtual string PrepareFormular(string Formular, string OperatorRegEx)
{
int locBracketCounter = 0;
//Klammern überprüfen
foreach (char locChar in Formular.ToCharArray())
{
if (locChar == '(')
{
locBracketCounter += 1;
}
if (locChar == ')')
{
locBracketCounter -= 1;
if (locBracketCounter < 0)
{
SyntaxErrorException up = new SyntaxErrorException("Too many closing brackets.");
throw up;
}
}
}
if (locBracketCounter > 0)
{
SyntaxErrorException up = new SyntaxErrorException("An open bracket was not closed.");
throw up;
}
//White-Spaces entfernen
Formular = Regex.Replace(Formular, "\\s", "");
//Vorzeichen verarbeiten
if (Formular.StartsWith("-") || Formular.StartsWith("+"))
{
Formular = Formular.Insert(0, "0");
}
//Sonderfall negative Klammer
Formular = Regex.Replace(Formular, "\\(-\\(", "(0-(");
return(Regex.Replace(Formular, "(?<operator>[" + OperatorRegEx + "\\(])-(?<zahl>[\\d\\.\\,]*)", "${operator}((0-1)*${zahl})"));
}
//Überschreibbare Funktion, die die Formelauswertung steuert.
protected virtual string Parse(string Formular, string OperatorRegEx)
{
string locTemp = null;
Match locTerm = null;
Match locFuncName = null;
MatchCollection locMoreInnerTerms = null;
List <double> locPreliminaryResult = new List <double>();
bool locFuncFound = false;
string locOperatorRegEx = "\\([\\d\\;" + OperatorRegEx + "]*\\)";
FormulaEvaluatorFunction adf = null;
locTerm = Regex.Match(Formular, locOperatorRegEx);
if (!string.IsNullOrEmpty(locTerm.Value))
{
locTemp = Formular.Substring(0, locTerm.Index);
//Befindet sich ein Funktionsname davor?
locFuncName = Regex.Match(locTemp, "[a-zA-Z]*", RegexOptions.RightToLeft);
//Gibt es mehrere, durch ; getrennte Parameter?
locMoreInnerTerms = Regex.Matches(locTerm.Value, "[\\d" + OperatorRegEx + "]*[;|\\)]");
//Jeden Parameterterm auswerten und zum Parameter-Array hinzufügen
foreach (Match locMatch in locMoreInnerTerms)
{
locTemp = locMatch.Value;
locTemp = locTemp.Replace(";", "").Replace(")", "");
locPreliminaryResult.Add(ParseSimpleTerm(locTemp));
}
//Möglicher Syntaxfehler: Mehrere Parameter, aber keine Funktion
if (string.IsNullOrEmpty(locFuncName.Value) && locMoreInnerTerms.Count > 1)
{
SyntaxErrorException up = new SyntaxErrorException("Found bracket pairs without a function!");
throw up;
}
if (!string.IsNullOrEmpty(locFuncName.Value))
{
//Funktionsnamen suchen
locFuncFound = false;
foreach (FormulaEvaluatorFunction adfWithinLoop in myFunctions)
{
adf = adfWithinLoop;
if (adfWithinLoop.FunctionName.ToUpper() == locFuncName.Value.ToUpper())
{
locFuncFound = true;
break;
}
}
if (locFuncFound == false)
{
SyntaxErrorException up = new SyntaxErrorException("Function not found!");
throw up;
}
else
{
Formular = Formular.Replace(locFuncName.Value + locTerm.Value, myConstEnumCounter.ToString("000"));
double[] locArgs = new double[locPreliminaryResult.Count];
locPreliminaryResult.CopyTo(locArgs);
//Diese Warnung bezieht sich auf einen hypothetischen Fall,
//der aber nie eintreten kann! :-)
myConsts.Add(adf.Operate(locArgs));
myConstEnumCounter += 1;
}
}
else
{
Formular = Formular.Replace(locTerm.Value, myConstEnumCounter.ToString("000"));
myConsts.Add(Convert.ToDouble(locPreliminaryResult[0]));
myConstEnumCounter += 1;
}
}
else
{
return(Formular);
}
Formular = Parse(Formular, OperatorRegEx);
return(Formular);
}
