/// <summary>
/// Executes the function based upon the name of the function
/// </summary>
/// <param name="name">name of the function to execute</param>
/// <param name="p">parameter list</param>
/// <returns>returned value of executed function</returns>
//[SuppressMessage("Microsoft.Maintainability", "CA1502:AvoidExcessiveComplexity")]
private object ExecuteFunction(string name, object[] p)
{
object[] parameters = null;
if (p != null)
{
parameters = (object[])p.Clone();
for (int x = 0; x < parameters.Length; x++)
if (parameters[x] is IExpression)
parameters[x] = ((IExpression)parameters[x]).Evaluate();
}
switch (name.ToLower(CultureInfo.CurrentCulture))
{
// Math functions
case "sin": return Math.Sin(Convert.ToDouble(parameters[0], CultureInfo.CurrentCulture));
case "cos": return Math.Cos(Convert.ToDouble(parameters[0], CultureInfo.CurrentCulture));
case "tan": return Math.Tan(Convert.ToDouble(parameters[0], CultureInfo.CurrentCulture));
case "sec": return 1 / Math.Cos(Convert.ToDouble(parameters[0], CultureInfo.CurrentCulture));
case "csc": return 1 / Math.Sin(Convert.ToDouble(parameters[0], CultureInfo.CurrentCulture));
case "cot": return 1 / Math.Tan(Convert.ToDouble(parameters[0], CultureInfo.CurrentCulture));
case "asin": return Math.Asin(Convert.ToDouble(parameters[0], CultureInfo.CurrentCulture));
case "acos": return Math.Acos(Convert.ToDouble(parameters[0], CultureInfo.CurrentCulture));
case "atan": return Math.Atan(Convert.ToDouble(parameters[0], CultureInfo.CurrentCulture));
case "sinh": return Math.Sinh(Convert.ToDouble(parameters[0], CultureInfo.CurrentCulture));
case "cosh": return Math.Cosh(Convert.ToDouble(parameters[0], CultureInfo.CurrentCulture));
case "tanh": return Math.Tanh(Convert.ToDouble(parameters[0], CultureInfo.CurrentCulture));
case "abs": return Math.Abs(Convert.ToDouble(parameters[0], CultureInfo.CurrentCulture));
case "sqrt": return Math.Sqrt(Convert.ToDouble(parameters[0], CultureInfo.CurrentCulture));
case "ciel": return Math.Ceiling(Convert.ToDouble(parameters[0], CultureInfo.CurrentCulture));
case "floor": return Math.Floor(Convert.ToDouble(parameters[0], CultureInfo.CurrentCulture));
case "exp": return Math.Exp(Convert.ToDouble(parameters[0], CultureInfo.CurrentCulture));
case "log10": return Math.Log10(Convert.ToDouble(parameters[0], CultureInfo.CurrentCulture));
case "log": return (parameters.Length > 1) ?
Math.Log(Convert.ToDouble(parameters[0], CultureInfo.CurrentCulture), Convert.ToDouble(parameters[1], CultureInfo.CurrentCulture)) :
Math.Log(Convert.ToDouble(parameters[0], CultureInfo.CurrentCulture));
case "max": return Math.Max(Convert.ToDouble(parameters[0], CultureInfo.CurrentCulture), Convert.ToDouble(parameters[1], CultureInfo.CurrentCulture));
case "min": return Math.Min(Convert.ToDouble(parameters[0], CultureInfo.CurrentCulture), Convert.ToDouble(parameters[1], CultureInfo.CurrentCulture));
case "pow": return Math.Pow(Convert.ToDouble(parameters[0], CultureInfo.CurrentCulture), Convert.ToDouble(parameters[1], CultureInfo.CurrentCulture));
case "round": return (parameters.Length > 1) ?
Math.Round(Convert.ToDouble(parameters[0], CultureInfo.CurrentCulture), Convert.ToInt32(parameters[1], CultureInfo.CurrentCulture)) :
Math.Round(Convert.ToDouble(parameters[0], CultureInfo.CurrentCulture));
//case "trunc": return Math.Truncate(Convert.ToDouble(parameters[0], CultureInfo.CurrentCulture));
case "e": return Math.E;
case "pi": return Math.PI;
//DateTime functions
case "now": return DateTime.Now;
case "today": return DateTime.Today;
case "mindate": return DateTime.MinValue;
case "maxdate": return DateTime.MaxValue;
case "monthname": return (new DateTime(2000, Convert.ToInt32(parameters[0]), 1)).ToString("MMMM");
case "adddays": return Convert.ToDateTime(parameters[0]).AddDays(Convert.ToInt32(parameters[1]));
case "addmonths": return Convert.ToDateTime(parameters[0]).AddMonths(Convert.ToInt32(parameters[1]));
case "addyears": return Convert.ToDateTime(parameters[0]).AddYears(Convert.ToInt32(parameters[1]));
case "addhours": return Convert.ToDateTime(parameters[0]).AddHours(Convert.ToInt32(parameters[1]));
case "addminutes": return Convert.ToDateTime(parameters[0]).AddMinutes(Convert.ToInt32(parameters[1]));
case "addseconds": return Convert.ToDateTime(parameters[0]).AddSeconds(Convert.ToInt32(parameters[1]));
//Formatting Functions
case "fmtnum": return Convert.ToDouble(parameters[0], CultureInfo.CurrentCulture).ToString("" + parameters[1], CultureInfo.CurrentCulture);
case "fmtdate": return Convert.ToDateTime(parameters[0], CultureInfo.CurrentCulture).ToString("" + parameters[1], CultureInfo.CurrentCulture);
//Numerical Expression Evaluation
case "expr":
{
ExpressionEval eval = new ExpressionEval("" + parameters[0]);
eval.AdditionalFunctionEventHandler += this.AdditionalFunctionEventHandler;
eval._variables = this._variables;
return eval.Evaluate();
}
//Casting Functions
case "cdbl": return Convert.ToDouble (parameters[0], CultureInfo.CurrentCulture);
case "cint": return Convert.ToInt32 (parameters[0], CultureInfo.CurrentCulture);
case "clong": return Convert.ToInt64 (parameters[0], CultureInfo.CurrentCulture);
case "cuint": return Convert.ToUInt32 (parameters[0], CultureInfo.CurrentCulture);
case "culong": return Convert.ToUInt64 (parameters[0], CultureInfo.CurrentCulture);
case "cdatetime": return Convert.ToDateTime(parameters[0], CultureInfo.CurrentCulture);
case "str": return parameters[0].ToString();
//Logical Functions
case "iif": return Iif(parameters);
case "case": return Case(parameters);
//security fucntions
case "currentuserid": return WindowsIdentity.GetCurrent().Name.ToLower() ;
default: return AdditionalFunctionHelper(name, parameters);
}
}
/// <summary>
/// Static version of the Expression Evaluator
/// </summary>
/// <param name="expression">expression to be evaluated</param>
/// <param name="handler">attach a custom function handler</param>
/// <returns></returns>
public static object Evaluate(string expression, AdditionalFunctionEventHandler handler)
{
ExpressionEval expr = new ExpressionEval(expression);
expr.AdditionalFunctionEventHandler += handler;
return expr.Evaluate();
}
private static bool performComparison(string[] values)
{
string comparisonString = "";
string tempVar;
bool errorFlag = false;
for (int i = 0; i < values.Length; i++)
{
//Console.WriteLine(values[i]);
if (values[i].Equals(".lt.")) { values[i] = " < "; }
else if (values[i].Equals(".gt.")) { values[i] = " > "; }
else if (values[i].Equals(".eq.")) { values[i] = " == "; }
else if (values[i].Equals(".le.")) { values[i] = " <= "; }
else if (values[i].Equals(".ge.")) { values[i] = " >= "; }
else if (values[i].Equals(".ne.")) { values[i] = " != "; }
else if (values[i].Equals(".and.")) { values[i] = " && "; }
else if (values[i].Equals(".or.")) { values[i] = " || "; }
else if (values[i].Equals(".not.")) { values[i] = " ! "; }
else if (isVariableName(values[i])) {
if (variables.ContainsKey(values[i])) { variables.TryGetValue(values[i], out tempVar); values[i] = tempVar; }
else { errorFlag = true; }
}
else if (isString(values[i])) { values[i] = values[i].Replace('"', '\''); } //.Trim('\'')
//Console.WriteLine(values[i]);
}
foreach (string s in values) { comparisonString += s; }
//Console.WriteLine(comparisonString);
if (!errorFlag)
{
ExpressionEval expr = new ExpressionEval(comparisonString);
object result = expr.Evaluate();
//Console.WriteLine(result);
return (bool)result;
}
else
{
return false;
}
}
/// <summary>
/// Static version of the Expression Evaluator
/// </summary>
/// <param name="expression">expression to be evaluated</param>
/// <returns></returns>
public static object Evaluate(string expressionString)
{
ExpressionEval expression = new ExpressionEval(expressionString);
return expression.Evaluate();
}