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ExpressionEvaluator.cs
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ExpressionEvaluator.cs
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/******************************************************************************************************
Title : ExpressionEvaluator (https://github.com/codingseb/ExpressionEvaluator)
Version : 1.4.40.0
(if last digit (the forth) is not a zero, the version is an intermediate version and can be unstable)
Author : Coding Seb
Licence : MIT (https://github.com/codingseb/ExpressionEvaluator/blob/master/LICENSE.md)
*******************************************************************************************************/
using System;
using System.Collections;
using System.Collections.Concurrent;
using System.Collections.Generic;
using System.ComponentModel;
using System.Dynamic;
using System.Globalization;
using System.Linq;
using System.Reflection;
using System.Runtime.CompilerServices;
using System.Runtime.ExceptionServices;
using System.Runtime.InteropServices;
using System.Text;
using System.Text.RegularExpressions;
namespace CodingSeb.ExpressionEvaluator
{
/// <summary>
/// This class allow to evaluate a string math or pseudo C# expression/script
/// </summary>
public partial class ExpressionEvaluator
{
#region Regex declarations
protected static readonly Regex varOrFunctionRegEx = new Regex(@"^((?<sign>[+-])|(?<prefixOperator>[+][+]|--)|(?<varKeyword>var)\s+|(?<dynamicKeyword>dynamic)\s+|((?<nullConditional>[?])?(?<inObject>\.))?)(?<name>[\p{L}_](?>[\p{L}_0-9]*))(?>\s*)((?<assignationOperator>(?<assignmentPrefix>[+\-*/%&|^]|<<|>>|\?\?)?=(?![=>]))|(?<postfixOperator>([+][+]|--)(?![\p{L}_0-9]))|((?<isgeneric>[<](?>([\p{L}_](?>[\p{L}_0-9]*)|(?>\s+)|[,\.])+|(?<gentag>[<])|(?<-gentag>[>]))*(?(gentag)(?!))[>])?(?<isfunction>[(])?))", RegexOptions.IgnoreCase | RegexOptions.Compiled);
//language=regex
protected const string numberRegexOrigPattern = @"^(?<sign>[+-])?([0-9][0-9_{1}]*[0-9]|\d)(?<hasdecimal>{0}?([0-9][0-9_]*[0-9]|\d)(e[+-]?([0-9][0-9_]*[0-9]|\d))?)?(?<type>ul|[fdulm])?";
protected string numberRegexPattern;
protected static readonly Regex otherBasesNumberRegex = new Regex("^(?<sign>[+-])?(?<value>0(?<type>x)([0-9a-f][0-9a-f_]*[0-9a-f]|[0-9a-f])|0(?<type>b)([01][01_]*[01]|[01]))", RegexOptions.IgnoreCase | RegexOptions.Compiled);
protected static readonly Regex stringBeginningRegex = new Regex("^(?<interpolated>[$])?(?<escaped>[@])?[\"]", RegexOptions.Compiled);
protected static readonly Regex internalCharRegex = new Regex(@"^['](\\[\\'0abfnrtv]|[^'])[']", RegexOptions.Compiled);
protected static readonly Regex indexingBeginningRegex = new Regex(@"^(?<nullConditional>[?])?\[", RegexOptions.Compiled);
protected static readonly Regex arrayTypeDetectionRegex = new Regex(@"^(\s*(\[(?>(?>\s+)|[,])*)\])+", RegexOptions.Compiled);
protected static readonly Regex assignationOrPostFixOperatorRegex = new Regex(@"^(?>\s*)((?<assignmentPrefix>[+\-*/%&|^]|<<|>>|\?\?)?=(?![=>])|(?<postfixOperator>([+][+]|--)(?![\p{L}_0-9])))");
protected static readonly Regex genericsDecodeRegex = new Regex("(?<name>[^,<>]+)(?<isgeneric>[<](?>[^<>]+|(?<gentag>[<])|(?<-gentag>[>]))*(?(gentag)(?!))[>])?", RegexOptions.Compiled);
protected static readonly Regex genericsEndOnlyOneTrim = new Regex(@"(?>\s*)[>](?>\s*)$", RegexOptions.Compiled);
protected static readonly Regex endOfStringWithDollar = new Regex("^([^\"{\\\\]|\\\\[\\\\\"0abfnrtv])*[\"{]", RegexOptions.Compiled);
protected static readonly Regex endOfStringWithoutDollar = new Regex("^([^\"\\\\]|\\\\[\\\\\"0abfnrtv])*[\"]", RegexOptions.Compiled);
protected static readonly Regex endOfStringWithDollarWithAt = new Regex("^[^\"{]*[\"{]", RegexOptions.Compiled);
protected static readonly Regex endOfStringWithoutDollarWithAt = new Regex("^[^\"]*[\"]", RegexOptions.Compiled);
protected static readonly Regex endOfStringInterpolationRegex = new Regex("^('\"'|[^}\"])*[}\"]", RegexOptions.Compiled);
protected static readonly Regex stringBeginningForEndBlockRegex = new Regex("[$]?[@]?[\"]$", RegexOptions.Compiled);
protected static readonly Regex lambdaExpressionRegex = new Regex(@"^(?>\s*)(?<args>((?>\s*)[(](?>\s*)([\p{L}_](?>[\p{L}_0-9]*)(?>\s*)([,](?>\s*)[\p{L}_][\p{L}_0-9]*(?>\s*))*)?[)])|[\p{L}_](?>[\p{L}_0-9]*))(?>\s*)=>(?<expression>.*)$", RegexOptions.Singleline | RegexOptions.Compiled);
protected static readonly Regex lambdaArgRegex = new Regex(@"[\p{L}_](?>[\p{L}_0-9]*)", RegexOptions.Compiled);
protected static readonly Regex initInNewBeginningRegex = new Regex(@"^(?>\s*){", RegexOptions.Compiled);
protected static readonly Regex functionArgKeywordsRegex = new Regex(@"^\s*(?<keyword>out|ref|in)\s+((?<typeName>[\p{L}_][\p{L}_0-9\.\[\]<>]*[?]?)\s+(?=[\p{L}_]))?(?<toEval>(?<varName>[\p{L}_](?>[\p{L}_0-9]*))\s*(=.*)?)$", RegexOptions.Compiled | RegexOptions.IgnoreCase);
protected static readonly Regex instanceCreationWithNewKeywordRegex = new Regex(@"^new(?=[^\w])\s*((?<isAnonymous>[{{])|((?<name>[\p{L}_][\p{L}_0-9\.]*)(?>\s*)(?<isgeneric>[<](?>[^<>]+|(?<gentag>[<])|(?<-gentag>[>]))*(?(gentag)(?!))[>])?(?>\s*)((?<isfunction>[(])|(?<isArray>\[)|(?<isInit>[{{]))?))", RegexOptions.IgnoreCase | RegexOptions.Compiled);
protected string CastRegexPattern { get { return @"^\((?>\s*)(?<typeName>[\p{L}_][\p{L}_0-9\.\[\]<>]*[?]?)(?>\s*)\)"; } }
// To remove comments in scripts based on https://stackoverflow.com/questions/3524317/regex-to-strip-line-comments-from-c-sharp/3524689#3524689
//language=regex
protected const string blockComments = @"/\*(.*?)\*/";
//language=regex
protected const string lineComments = @"//[^\r\n]*";
//language=regex
protected const string stringsIgnore = @"""((\\[^\n]|[^""\n])*)""";
//language=regex
protected const string verbatimStringsIgnore = @"@(""[^""]*"")+";
protected static readonly Regex removeCommentsRegex = new Regex($"{blockComments}|{lineComments}|{stringsIgnore}|{verbatimStringsIgnore}", RegexOptions.Singleline | RegexOptions.Compiled);
protected static readonly Regex newLineCharsRegex = new Regex(@"\r\n|\r|\n", RegexOptions.Compiled);
// For script only
protected static readonly Regex blockKeywordsBeginningRegex = new Regex(@"^(?>\s*)(?<keyword>while|for|foreach|if|else(?>\s*)if|catch)(?>\s*)[(]", RegexOptions.IgnoreCase | RegexOptions.Compiled);
protected static readonly Regex foreachParenthisEvaluationRegex = new Regex(@"^(?>\s*)(?<variableName>[\p{L}_](?>[\p{L}_0-9]*))(?>\s*)(?<in>in)(?>\s*)(?<collection>.*)", RegexOptions.IgnoreCase | RegexOptions.Compiled);
protected static readonly Regex blockKeywordsWithoutParenthesesBeginningRegex = new Regex(@"^(?>\s*)(?<keyword>else|do|try|finally)(?![\p{L}_0-9])", RegexOptions.IgnoreCase | RegexOptions.Compiled);
protected static readonly Regex blockBeginningRegex = new Regex(@"^(?>\s*)[{]", RegexOptions.Compiled);
protected static readonly Regex returnKeywordRegex = new Regex(@"^return((?>\s*)|\()", RegexOptions.IgnoreCase | RegexOptions.Singleline | RegexOptions.Compiled);
protected static readonly Regex nextIsEndOfExpressionRegex = new Regex(@"^(?>\s*)[;]", RegexOptions.Compiled);
#endregion
#region enums (if else blocks states)
protected enum IfBlockEvaluatedState
{
NoBlockEvaluated,
If,
ElseIf
}
protected enum TryBlockEvaluatedState
{
NoBlockEvaluated,
Try,
Catch
}
#endregion
#region Dictionaries declarations (Primary types, number suffix, escaped chars, operators management, default vars and functions)
protected static readonly IDictionary<string, Type> primaryTypesDict = new Dictionary<string, Type>()
{
{ "object", typeof(object) },
{ "string", typeof(string) },
{ "bool", typeof(bool) },
{ "bool?", typeof(bool?) },
{ "byte", typeof(byte) },
{ "byte?", typeof(byte?) },
{ "char", typeof(char) },
{ "char?", typeof(char?) },
{ "decimal", typeof(decimal) },
{ "decimal?", typeof(decimal?) },
{ "double", typeof(double) },
{ "double?", typeof(double?) },
{ "short", typeof(short) },
{ "short?", typeof(short?) },
{ "int", typeof(int) },
{ "int?", typeof(int?) },
{ "long", typeof(long) },
{ "long?", typeof(long?) },
{ "sbyte", typeof(sbyte) },
{ "sbyte?", typeof(sbyte?) },
{ "float", typeof(float) },
{ "float?", typeof(float?) },
{ "ushort", typeof(ushort) },
{ "ushort?", typeof(ushort?) },
{ "uint", typeof(uint) },
{ "uint?", typeof(uint?) },
{ "ulong", typeof(ulong) },
{ "ulong?", typeof(ulong?) },
{ "void", typeof(void) }
};
// Based on https://docs.microsoft.com/en-us/previous-versions/visualstudio/visual-studio-2012/y5b434w4(v=vs.110)?redirectedfrom=MSDN
protected static readonly IDictionary<Type, Type[]> implicitCastDict = new Dictionary<Type, Type[]>
{
{ typeof(sbyte), new Type[] { typeof(short), typeof(int), typeof(long), typeof(float), typeof(double), typeof(decimal) } },
{ typeof(byte), new Type[] { typeof(short), typeof(ushort), typeof(int), typeof(uint), typeof(long), typeof(ulong), typeof(float), typeof(double), typeof(decimal) } },
{ typeof(short), new Type[] { typeof(int), typeof(long), typeof(float), typeof(double), typeof(decimal) } },
{ typeof(ushort), new Type[] { typeof(int), typeof(uint), typeof(long), typeof(ulong), typeof(float), typeof(double), typeof(decimal) } },
{ typeof(int), new Type[] { typeof(long), typeof(float), typeof(double), typeof(decimal) } },
{ typeof(uint), new Type[] {typeof(long), typeof(ulong), typeof(float), typeof(double), typeof(decimal) } },
{ typeof(long), new Type[] { typeof(float), typeof(double), typeof(decimal) } },
{ typeof(char), new Type[] { typeof(ushort), typeof(int), typeof(uint), typeof(long), typeof(ulong), typeof(float), typeof(double), typeof(decimal) } },
{ typeof(float), new Type[] { typeof(double) } },
{ typeof(ulong), new Type[] { typeof(float), typeof(double), typeof(decimal) } },
};
protected static readonly IDictionary<string, Func<string, CultureInfo, object>> numberSuffixToParse = new Dictionary<string, Func<string, CultureInfo, object>>(StringComparer.OrdinalIgnoreCase) // Always Case insensitive, like in C#
{
{ "f", (number, culture) => float.Parse(number, NumberStyles.Any, culture) },
{ "d", (number, culture) => double.Parse(number, NumberStyles.Any, culture) },
{ "u", (number, culture) => uint.Parse(number, NumberStyles.Any, culture) },
{ "l", (number, culture) => long.Parse(number, NumberStyles.Any, culture) },
{ "ul", (number, culture) => ulong.Parse(number, NumberStyles.Any, culture) },
{ "m", (number, culture) => decimal.Parse(number, NumberStyles.Any, culture) }
};
protected static readonly IDictionary<char, string> stringEscapedCharDict = new Dictionary<char, string>()
{
{ '\\', @"\" },
{ '"', "\"" },
{ '0', "\0" },
{ 'a', "\a" },
{ 'b', "\b" },
{ 'f', "\f" },
{ 'n', "\n" },
{ 'r', "\r" },
{ 't', "\t" },
{ 'v', "\v" }
};
protected static readonly IDictionary<char, char> charEscapedCharDict = new Dictionary<char, char>()
{
{ '\\', '\\' },
{ '\'', '\'' },
{ '0', '\0' },
{ 'a', '\a' },
{ 'b', '\b' },
{ 'f', '\f' },
{ 'n', '\n' },
{ 'r', '\r' },
{ 't', '\t' },
{ 'v', '\v' }
};
/// <summary>
/// OperatorsDictionaryInit() for values
/// </summary>
protected IDictionary<string, ExpressionOperator> operatorsDictionary = new Dictionary<string, ExpressionOperator>(StringComparer.Ordinal)
{
{ "+", ExpressionOperator.Plus },
{ "-", ExpressionOperator.Minus },
{ "*", ExpressionOperator.Multiply },
{ "/", ExpressionOperator.Divide },
{ "%", ExpressionOperator.Modulo },
{ "<", ExpressionOperator.Lower },
{ ">", ExpressionOperator.Greater },
{ "<=", ExpressionOperator.LowerOrEqual },
{ ">=", ExpressionOperator.GreaterOrEqual },
{ "is", ExpressionOperator.Is },
{ "==", ExpressionOperator.Equal },
{ "!=", ExpressionOperator.NotEqual },
{ "&&", ExpressionOperator.ConditionalAnd },
{ "||", ExpressionOperator.ConditionalOr },
{ "!", ExpressionOperator.LogicalNegation },
{ "~", ExpressionOperator.BitwiseComplement },
{ "&", ExpressionOperator.LogicalAnd },
{ "|", ExpressionOperator.LogicalOr },
{ "^", ExpressionOperator.LogicalXor },
{ "<<", ExpressionOperator.ShiftBitsLeft },
{ ">>", ExpressionOperator.ShiftBitsRight },
{ "??", ExpressionOperator.NullCoalescing },
};
protected static readonly IList<ExpressionOperator> leftOperandOnlyOperatorsEvaluationDictionary = new List<ExpressionOperator>();
protected static readonly IList<ExpressionOperator> rightOperandOnlyOperatorsEvaluationDictionary = new List<ExpressionOperator>()
{
ExpressionOperator.LogicalNegation,
ExpressionOperator.BitwiseComplement,
ExpressionOperator.UnaryPlus,
ExpressionOperator.UnaryMinus
};
protected IDictionary<string, ExpressionOperator> unaryOperatorsDictionary = new Dictionary<string, ExpressionOperator>()
{
{ "+", ExpressionOperator.UnaryPlus },
{ "-", ExpressionOperator.UnaryMinus }
};
protected virtual IList<ExpressionOperator> LeftOperandOnlyOperatorsEvaluationDictionary => leftOperandOnlyOperatorsEvaluationDictionary;
protected virtual IList<ExpressionOperator> RightOperandOnlyOperatorsEvaluationDictionary => rightOperandOnlyOperatorsEvaluationDictionary;
protected virtual IList<IDictionary<ExpressionOperator, Func<dynamic, dynamic, object>>> OperatorsEvaluations => operatorsEvaluations;
protected static readonly IList<IDictionary<ExpressionOperator, Func<dynamic, dynamic, object>>> operatorsEvaluations =
new List<IDictionary<ExpressionOperator, Func<dynamic, dynamic, object>>>()
{
new Dictionary<ExpressionOperator, Func<dynamic, dynamic, object>>()
{
{ExpressionOperator.UnaryPlus, (dynamic _, dynamic right) => +right },
{ExpressionOperator.UnaryMinus, (dynamic _, dynamic right) => -right },
{ExpressionOperator.LogicalNegation, (dynamic _, dynamic right) => !right },
{ExpressionOperator.BitwiseComplement, (dynamic _, dynamic right) => ~right },
{ExpressionOperator.Cast, (dynamic left, dynamic right) => ChangeType(right, left) },
},
new Dictionary<ExpressionOperator, Func<dynamic, dynamic, object>>()
{
{ExpressionOperator.Multiply, (dynamic left, dynamic right) => left * right },
{ExpressionOperator.Divide, (dynamic left, dynamic right) => left / right },
{ExpressionOperator.Modulo, (dynamic left, dynamic right) => left % right },
},
new Dictionary<ExpressionOperator, Func<dynamic, dynamic, object>>()
{
{ExpressionOperator.Plus, (dynamic left, dynamic right) => left + right },
{ExpressionOperator.Minus, (dynamic left, dynamic right) => left - right },
},
new Dictionary<ExpressionOperator, Func<dynamic, dynamic, object>>()
{
{ExpressionOperator.ShiftBitsLeft, (dynamic left, dynamic right) => left << right },
{ExpressionOperator.ShiftBitsRight, (dynamic left, dynamic right) => left >> right },
},
new Dictionary<ExpressionOperator, Func<dynamic, dynamic, object>>()
{
{ExpressionOperator.Lower, (dynamic left, dynamic right) => left < right },
{ExpressionOperator.Greater, (dynamic left, dynamic right) => left > right },
{ExpressionOperator.LowerOrEqual, (dynamic left, dynamic right) => left <= right },
{ExpressionOperator.GreaterOrEqual, (dynamic left, dynamic right) => left >= right },
{ExpressionOperator.Is, (dynamic left, dynamic right) => left != null && (((ClassOrEnumType)right).Type).IsAssignableFrom(left.GetType()) },
},
new Dictionary<ExpressionOperator, Func<dynamic, dynamic, object>>()
{
{ExpressionOperator.Equal, (dynamic left, dynamic right) => left == right },
{ExpressionOperator.NotEqual, (dynamic left, dynamic right) => left != right },
},
new Dictionary<ExpressionOperator, Func<dynamic, dynamic, object>>()
{
{ExpressionOperator.LogicalAnd, (dynamic left, dynamic right) => left & right },
},
new Dictionary<ExpressionOperator, Func<dynamic, dynamic, object>>()
{
{ExpressionOperator.LogicalXor, (dynamic left, dynamic right) => left ^ right },
},
new Dictionary<ExpressionOperator, Func<dynamic, dynamic, object>>()
{
{ExpressionOperator.LogicalOr, (dynamic left, dynamic right) => left | right },
},
new Dictionary<ExpressionOperator, Func<dynamic, dynamic, object>>()
{
{ExpressionOperator.ConditionalAnd, (dynamic left, dynamic right) => {
if ( left is BubbleExceptionContainer leftExceptionContainer)
{
leftExceptionContainer.Throw();
return null; // this line is never reached
}
else if (!left)
{
return false;
}
else if (right is BubbleExceptionContainer rightExceptionContainer)
{
rightExceptionContainer.Throw();
return null; // this line is never reached
}
else
{
return left && right;
}
} },
},
new Dictionary<ExpressionOperator, Func<dynamic, dynamic, object>>()
{
{ExpressionOperator.ConditionalOr, (dynamic left, dynamic right) => {
if ( left is BubbleExceptionContainer leftExceptionContainer)
{
leftExceptionContainer.Throw();
return null; // this line is never reached
}
else if (left)
{
return true;
}
else if (right is BubbleExceptionContainer rightExceptionContainer)
{
rightExceptionContainer.Throw();
return null; // this line is never reached
}
else
{
return left || right;
}
} },
},
new Dictionary<ExpressionOperator, Func<dynamic, dynamic, object>>()
{
{ExpressionOperator.NullCoalescing, (dynamic left, dynamic right) => left ?? right },
},
};
protected IDictionary<string, object> defaultVariables = new Dictionary<string, object>(StringComparer.Ordinal)
{
{ "Pi", Math.PI },
{ "E", Math.E },
{ "null", null},
{ "true", true },
{ "false", false },
{ "this", null }
};
protected IDictionary<string, Func<double, double>> simpleDoubleMathFuncsDictionary = new Dictionary<string, Func<double, double>>(StringComparer.Ordinal)
{
{ "Abs", Math.Abs },
{ "Acos", Math.Acos },
{ "Asin", Math.Asin },
{ "Atan", Math.Atan },
{ "Ceiling", Math.Ceiling },
{ "Cos", Math.Cos },
{ "Cosh", Math.Cosh },
{ "Exp", Math.Exp },
{ "Floor", Math.Floor },
{ "Log10", Math.Log10 },
{ "Sin", Math.Sin },
{ "Sinh", Math.Sinh },
{ "Sqrt", Math.Sqrt },
{ "Tan", Math.Tan },
{ "Tanh", Math.Tanh },
{ "Truncate", Math.Truncate },
};
protected IDictionary<string, Func<double, double, double>> doubleDoubleMathFuncsDictionary = new Dictionary<string, Func<double, double, double>>(StringComparer.Ordinal)
{
{ "Atan2", Math.Atan2 },
{ "IEEERemainder", Math.IEEERemainder },
{ "Log", Math.Log },
{ "Pow", Math.Pow },
};
protected IDictionary<string, Func<ExpressionEvaluator, List<string>, object>> complexStandardFuncsDictionary = new Dictionary<string, Func<ExpressionEvaluator, List<string>, object>>(StringComparer.Ordinal)
{
{ "Array", (self, args) => args.ConvertAll(self.Evaluate).ToArray() },
{ "ArrayOfType", (self, args) =>
{
Array sourceArray = args.Skip(1).Select(self.Evaluate).ToArray();
Array typedArray = Array.CreateInstance((Type)self.Evaluate(args[0]), sourceArray.Length);
Array.Copy(sourceArray, typedArray, sourceArray.Length);
return typedArray;
}
},
{ "Avg", (self, args) => args.ConvertAll(arg => Convert.ToDouble(self.Evaluate(arg))).Sum() / (double)args.Count },
{ "default", (self, args) =>
{
object argValue = self.Evaluate(args[0]);
if (argValue is ClassOrEnumType classOrTypeName)
return Activator.CreateInstance(classOrTypeName.Type);
else
return null;
}
},
{ "in", (self, args) => args.Skip(1).ToList().ConvertAll(self.Evaluate).Contains(self.Evaluate(args[0])) },
{ "List", (self, args) => args.ConvertAll(self.Evaluate) },
{ "ListOfType", (self, args) =>
{
Type type = (Type)self.Evaluate(args[0]);
Array sourceArray = args.Skip(1).Select(self.Evaluate).ToArray();
Array typedArray = Array.CreateInstance(type, sourceArray.Length);
Array.Copy(sourceArray, typedArray, sourceArray.Length);
Type typeOfList = typeof(List<>).MakeGenericType(type);
object list = Activator.CreateInstance(typeOfList);
typeOfList.GetMethod("AddRange").Invoke(list, new object[]{ typedArray });
return list;
}
},
{ "Max", (self, args) => args.ConvertAll(arg => Convert.ToDouble(self.Evaluate(arg))).Max() },
{ "Min", (self, args) => args.ConvertAll(arg => Convert.ToDouble(self.Evaluate(arg))).Min() },
{ "new", (self, args) =>
{
List<object> cArgs = args.ConvertAll(self.Evaluate);
return cArgs[0] is ClassOrEnumType classOrEnumType ? Activator.CreateInstance(classOrEnumType.Type, cArgs.Skip(1).ToArray()) : null;
}
},
{ "Round", (self, args) =>
{
if(args.Count == 3)
{
return Math.Round(Convert.ToDouble(self.Evaluate(args[0])), Convert.ToInt32(self.Evaluate(args[1])), (MidpointRounding)self.Evaluate(args[2]));
}
else if(args.Count == 2)
{
object arg2 = self.Evaluate(args[1]);
if(arg2 is MidpointRounding midpointRounding)
return Math.Round(Convert.ToDouble(self.Evaluate(args[0])), midpointRounding);
else
return Math.Round(Convert.ToDouble(self.Evaluate(args[0])), Convert.ToInt32(arg2));
}
else if(args.Count == 1) { return Math.Round(Convert.ToDouble(self.Evaluate(args[0]))); }
else
{
throw new ArgumentException();
}
}
},
{ "Sign", (self, args) => Math.Sign(Convert.ToDouble(self.Evaluate(args[0]))) },
{ "sizeof", (self, args) =>
{
Type type = ((ClassOrEnumType)self.Evaluate(args[0])).Type;
if(type == typeof(bool))
return 1;
else if(type == typeof(char))
return 2;
else
return Marshal.SizeOf(type);
}
},
{ "typeof", (self, args) => ((ClassOrEnumType)self.Evaluate(args[0])).Type },
};
#endregion
#region Caching
/// <summary>
/// if set to <c>true</c> use a cache for types that were resolved to resolve faster next time.<para/>
/// if set to <c>false</c> the cache of types resolution is not use for this instance of ExpressionEvaluator.<para/>
/// Default : false<para/>
/// The cache is the static Dictionary TypesResolutionCaching (so it is shared by all instances of ExpressionEvaluator that have CacheTypesResolutions enabled)
/// </summary>
public bool CacheTypesResolutions { get; set; }
/// <summary>
/// A shared cache for types resolution.
/// </summary>
public static IDictionary<string, Type> TypesResolutionCaching { get; set; } = new ConcurrentDictionary<string, Type>();
/// <summary>
/// Clear all ExpressionEvaluator caches
/// </summary>
public static void ClearAllCaches()
{
TypesResolutionCaching.Clear();
}
#endregion
#region Assemblies, Namespaces and types lists
private static IList<Assembly> staticAssemblies;
private IList<Assembly> assemblies;
/// <summary>
/// All assemblies needed to resolves Types<para/>
/// By default all assemblies loaded in the current AppDomain
/// </summary>
public virtual IList<Assembly> Assemblies
{
get { return assemblies ?? (assemblies = staticAssemblies) ?? (assemblies = staticAssemblies = AppDomain.CurrentDomain.GetAssemblies().ToList()); }
set { assemblies = value; }
}
/// <summary>
/// All Namespaces Where to find types<para/>
/// Equivalent of a <c>using Namespace;</c>
/// </summary>
public virtual IList<string> Namespaces { get; set; } = new List<string>()
{
"System",
"System.Linq",
"System.IO",
"System.Text",
"System.Text.RegularExpressions",
"System.ComponentModel",
"System.Dynamic",
"System.Collections",
"System.Collections.Generic",
"System.Collections.Specialized",
"System.Globalization"
};
/// <summary>
/// To add or remove specific types to manage in expression.
/// </summary>
public virtual IList<Type> Types { get; set; } = new List<Type>();
/// <summary>
/// A list of type to block an keep un usable in Expression Evaluation for security purpose
/// </summary>
public virtual IList<Type> TypesToBlock { get; set; } = new List<Type>();
/// <summary>
/// A list of statics types where to find extensions methods
/// </summary>
public virtual IList<Type> StaticTypesForExtensionsMethods { get; set; } = new List<Type>()
{
typeof(Enumerable) // For Linq extension methods
};
#endregion
#region Options
private bool optionCaseSensitiveEvaluationActive = true;
/// <summary>
/// If <c>true</c> all evaluation are case sensitives.<para/>
/// If <c>false</c> evaluations are case insensitive.<para/>
/// By default = true
/// </summary>
public bool OptionCaseSensitiveEvaluationActive
{
get { return optionCaseSensitiveEvaluationActive; }
set
{
optionCaseSensitiveEvaluationActive = value;
StringComparisonForCasing = optionCaseSensitiveEvaluationActive ? StringComparison.Ordinal : StringComparison.OrdinalIgnoreCase;
Variables = Variables;
operatorsDictionary = new Dictionary<string, ExpressionOperator>(operatorsDictionary, StringComparerForCasing);
defaultVariables = new Dictionary<string, object>(defaultVariables, StringComparerForCasing);
simpleDoubleMathFuncsDictionary = new Dictionary<string, Func<double, double>>(simpleDoubleMathFuncsDictionary, StringComparerForCasing);
doubleDoubleMathFuncsDictionary = new Dictionary<string, Func<double, double, double>>(doubleDoubleMathFuncsDictionary, StringComparerForCasing);
complexStandardFuncsDictionary = new Dictionary<string, Func<ExpressionEvaluator, List<string>, object>>(complexStandardFuncsDictionary, StringComparerForCasing);
}
}
/// <summary>
/// If <c>true</c> Variables dictionary is kept as given so variables are persist outside of the evaluator and the comparer for keys can be defined by the user<para/>
/// If <c>false</c> Variables dictionary references are copied internally to follow OptionCaseSensitiveEvaluationActive with an internal protected comparer for keys<para/>
/// By default = false
/// </summary>
public bool OptionVariablesPersistenceCustomComparer { get; set; }
protected StringComparison StringComparisonForCasing { get; set; } = StringComparison.Ordinal;
protected StringComparer StringComparerForCasing => OptionCaseSensitiveEvaluationActive ? StringComparer.Ordinal : StringComparer.OrdinalIgnoreCase;
/// <summary>
/// If <c>true</c> all numbers without decimal and suffixes evaluations will be done as double<para/>
/// If <c>false</c> Integers values without decimal and suffixes will be evaluate as int as in C# (Warning some operation can round values)<para/>
/// By default = false
/// </summary>
public bool OptionForceIntegerNumbersEvaluationsAsDoubleByDefault { get; set; }
private CultureInfo cultureInfoForNumberParsing = CultureInfo.InvariantCulture.Clone() as CultureInfo;
/// <summary>
/// The culture used to evaluate numbers.<para/>
/// Synchronized with OptionNumberParsingDecimalSeparator and OptionNumberParsingThousandSeparator.<para/>
/// So always set a full CultureInfo object and do not change CultureInfoForNumberParsing.NumberFormat.NumberDecimalSeparator and CultureInfoForNumberParsing.NumberFormat.NumberGroupSeparator properties directly.<para/>
/// Warning if using comma in separators change also OptionFunctionArgumentsSeparator and OptionInitializersSeparator otherwise it will create conflicts
/// </summary>
public CultureInfo CultureInfoForNumberParsing
{
get
{
return cultureInfoForNumberParsing;
}
set
{
cultureInfoForNumberParsing = value;
OptionNumberParsingDecimalSeparator = cultureInfoForNumberParsing.NumberFormat.NumberDecimalSeparator;
OptionNumberParsingThousandSeparator = cultureInfoForNumberParsing.NumberFormat.NumberGroupSeparator;
}
}
private string optionNumberParsingDecimalSeparator = ".";
/// <summary>
/// Allow to change the decimal separator of numbers when parsing expressions.<para/>
/// By default "."<para/>
/// Warning if using comma change also OptionFunctionArgumentsSeparator and OptionInitializersSeparator otherwise it will create conflicts.<para/>
/// Modify CultureInfoForNumberParsing.
/// </summary>
public string OptionNumberParsingDecimalSeparator
{
get => optionNumberParsingDecimalSeparator;
set
{
optionNumberParsingDecimalSeparator = value ?? ".";
CultureInfoForNumberParsing.NumberFormat.NumberDecimalSeparator = optionNumberParsingDecimalSeparator;
numberRegexPattern = string.Format(numberRegexOrigPattern,
optionNumberParsingDecimalSeparator != null ? Regex.Escape(optionNumberParsingDecimalSeparator) : ".",
optionNumberParsingThousandSeparator != null ? Regex.Escape(optionNumberParsingThousandSeparator) : "");
}
}
private string optionNumberParsingThousandSeparator = string.Empty;
/// <summary>
/// Allow to change the thousand separator of numbers when parsing expressions.<para/>
/// By default string.Empty<para/>
/// Warning if using comma change also OptionFunctionArgumentsSeparator and OptionInitializersSeparator otherwise it will create conflicts.<para/>
/// Modify CultureInfoForNumberParsing.
/// </summary>
public string OptionNumberParsingThousandSeparator
{
get => optionNumberParsingThousandSeparator;
set
{
optionNumberParsingThousandSeparator = value ?? string.Empty;
CultureInfoForNumberParsing.NumberFormat.NumberGroupSeparator = value;
numberRegexPattern = string.Format(numberRegexOrigPattern,
optionNumberParsingDecimalSeparator != null ? Regex.Escape(optionNumberParsingDecimalSeparator) : ".",
optionNumberParsingThousandSeparator != null ? Regex.Escape(optionNumberParsingThousandSeparator) : "");
}
}
/// <summary>
/// Allow to change the separator of functions arguments.<para/>
/// By default ","<para/>
/// Warning must to be changed if OptionNumberParsingDecimalSeparator = "," otherwise it will create conflicts<para/>
/// </summary>
public string OptionFunctionArgumentsSeparator { get; set; } = ",";
/// <summary>
/// Allow to change the separator of Object and collections Initialization between { and } after the keyword new.<para/>
/// By default ","<para/>
/// Warning must to be changed if OptionNumberParsingDecimalSeparator = "," otherwise it will create conflicts<para/>
/// </summary>
public string OptionInitializersSeparator { get; set; } = ",";
/// <summary>
/// if <c>true</c> allow to add the prefix Fluid or Fluent before void methods names to return back the instance on which the method is call.<para/>
/// if <c>false</c> unactive this functionality.<para/>
/// By default : true
/// </summary>
public bool OptionFluidPrefixingActive { get; set; } = true;
/// <summary>
/// if <c>AllowAll</c> Allow the use of any inline namespace that is available in memory (Can be slow, and is less secure).<para/>
/// if <c>AllowOnlyInlineNamespacesList</c> Allow only the use of inline namespace defined in <see cref="InlineNamespacesList"/><para/>
/// if <c>BlockOnlyInlineNamespacesList</c> Allow the use of any inline namespace that is available in memory that is not defined in <see cref="InlineNamespacesList"/><para/>
/// if <c>BlockAll</c> Unactive the use of inline namespaces<para/>
/// By default : <c>AllowAll</c>
/// </summary>
public InlineNamespacesEvaluationRule OptionInlineNamespacesEvaluationRule { get; set; } = InlineNamespacesEvaluationRule.AllowAll;
/// <summary>
/// This list is used to allow or block depending on <see cref="OptionInlineNamespacesEvaluationRule"/> a list of namespaces for inline writing.<para/>
/// The direct access of type depending on <see cref="Namespaces"/> is not affected by this list.
/// </summary>
public virtual IList<string> InlineNamespacesList { get; set; } = new List<string>();
private Func<ExpressionEvaluator, List<string>, object> newMethodMem;
/// <summary>
/// if <c>true</c> allow to create instance of object with the Default function new(ClassNam,...).<para/>
/// if <c>false</c> unactive this functionality.<para/>
/// By default : true
/// </summary>
public bool OptionNewFunctionEvaluationActive
{
get
{
return complexStandardFuncsDictionary.ContainsKey("new");
}
set
{
if (value && !complexStandardFuncsDictionary.ContainsKey("new"))
{
complexStandardFuncsDictionary["new"] = newMethodMem;
}
else if (!value && complexStandardFuncsDictionary.ContainsKey("new"))
{
newMethodMem = complexStandardFuncsDictionary["new"];
complexStandardFuncsDictionary.Remove("new");
}
}
}
/// <summary>
/// if <c>true</c> allow to create instance of object with the C# syntax new ClassName(...).<para/>
/// if <c>false</c> unactive this functionality.<para/>
/// By default : true
/// </summary>
public bool OptionNewKeywordEvaluationActive { get; set; } = true;
/// <summary>
/// if <c>true</c> allow to call static methods on classes.<para/>
/// if <c>false</c> unactive this functionality.<para/>
/// By default : true
/// </summary>
public bool OptionStaticMethodsCallActive { get; set; } = true;
/// <summary>
/// if <c>true</c> allow to get static properties on classes<para/>
/// if <c>false</c> unactive this functionality.<para/>
/// By default : true
/// </summary>
public bool OptionStaticPropertiesGetActive { get; set; } = true;
/// <summary>
/// if <c>true</c> allow to call instance methods on objects.<para/>
/// if <c>false</c> unactive this functionality.<para/>
/// By default : true
/// </summary>
public bool OptionInstanceMethodsCallActive { get; set; } = true;
/// <summary>
/// if <c>true</c> allow to get instance properties on objects<para/>
/// if <c>false</c> unactive this functionality.<para/>
/// By default : true
/// </summary>
public bool OptionInstancePropertiesGetActive { get; set; } = true;
/// <summary>
/// if <c>true</c> allow to get object at index or key like <c>IndexedObject[indexOrKey]</c><para/>
/// if <c>false</c> unactive this functionality.<para/>
/// By default : true
/// </summary>
public bool OptionIndexingActive { get; set; } = true;
/// <summary>
/// if <c>true</c> allow string interpretation with ""<para/>
/// if <c>false</c> unactive this functionality.<para/>
/// By default : true
/// </summary>
public bool OptionStringEvaluationActive { get; set; } = true;
/// <summary>
/// if <c>true</c> allow char interpretation with ''<para/>
/// if <c>false</c> unactive this functionality.<para/>
/// By default : true
/// </summary>
public bool OptionCharEvaluationActive { get; set; } = true;
/// <summary>
/// If <c>true</c> Evaluate function is callables in an expression.<para/>
/// If <c>false</c> Evaluate is not callable.<para/>
/// By default : true<para/>
/// if set to false for security (also ensure that ExpressionEvaluator type is in TypesToBlock list)
/// </summary>
public bool OptionEvaluateFunctionActive { get; set; } = true;
/// <summary>
/// If <c>true</c> allow to assign a value to a variable in the Variable disctionary with (=, +=, -=, *=, /=, %=, &=, |=, ^=, <<=, >>=, ++ or --)<para/>
/// If <c>false</c> unactive this functionality<para/>
/// By default : true
/// </summary>
public bool OptionVariableAssignationActive { get; set; } = true;
/// <summary>
/// If <c>true</c> allow to set/modify a property or a field value with (=, +=, -=, *=, /=, %=, &=, |=, ^=, <<=, >>=, ++ or --)<para/>
/// If <c>false</c> unactive this functionality<para/>
/// By default : true
/// </summary>
public bool OptionPropertyOrFieldSetActive { get; set; } = true;
/// <summary>
/// If <c>true</c> allow to assign a indexed element like Collections, List, Arrays and Dictionaries with (=, +=, -=, *=, /=, %=, &=, |=, ^=, <<=, >>=, ++ or --)<para/>
/// If <c>false</c> unactive this functionality<para/>
/// By default : true
/// </summary>
public bool OptionIndexingAssignationActive { get; set; } = true;
/// <summary>
/// If <c>true</c> ScriptEvaluate function is callables in an expression.<para/>
/// If <c>false</c> Evaluate is not callable.<para/>
/// By default : true<para/>
/// if set to false for security (also ensure that ExpressionEvaluator type is in TypesToBlock list)
/// </summary>
public bool OptionScriptEvaluateFunctionActive { get; set; } = true;
/// <summary>
/// Set How to react when the keyword return is not found in a script. when using ScriptEvaluate method<para/>
/// If <c>ReturnAutomaticallyLastEvaluatedExpression</c> ScriptEvaluate return automatically the last evaluated expression if no return keyword is met.<para/>
/// If <c>ReturnNull</c> return null if no return keyword is met.<para/>
/// If <c>ThrowSyntaxException</c> a exception is throw if no return keyword is met.<para/>
/// By default : ReturnAutomaticallyLastEvaluatedExpression;
/// </summary>
public OptionOnNoReturnKeywordFoundInScriptAction OptionOnNoReturnKeywordFoundInScriptAction { get; set; }
/// <summary>
/// If <c>true</c> ScriptEvaluate need to have a semicolon [;] after each expression.<para/>
/// If <c>false</c> Allow to omit the semicolon for the last expression of the script.<para/>
/// Default : true
/// </summary>
public bool OptionScriptNeedSemicolonAtTheEndOfLastExpression { get; set; } = true;
/// <summary>
/// If <c>true</c> Allow to access fields, properties and methods that are not declared public. (private, protected and internal)<para/>
/// If <c>false</c> Allow to access only to public members.<para/>
/// Default : false<para/>
/// Warning : This clearly break the encapsulation principle use this only if you know what you do.
/// </summary>
public bool OptionAllowNonPublicMembersAccess { get; set; }
/// <summary>
/// If <c>true</c> On unsuccessful call to an extension method, all defined overloads of that method are detected to resolve whether method is defined and called with wrong arguments or method is not defined.<para/>
/// If <c>false</c> Unsucessful call to an extension method will always result in "Method {name} is not defined on type {type}"<para/>
/// Default : true
/// </summary>
public bool OptionDetectExtensionMethodsOverloadsOnExtensionMethodNotFound { get; set; } = true;
/// <summary>
/// If <c>true</c> Allow to define multi expression lambda in Expressions (not in script)<para/>
/// If <c>false</c> Can only define simple expression lambda if not in script<para/>
/// Default value : <c>true</c>
/// </summary>
public bool OptionCanDeclareMultiExpressionsLambdaInSimpleExpressionEvaluate { get; set; } = true;
#endregion
#region Reflection flags
protected virtual BindingFlags InstanceBindingFlag
{
get
{
BindingFlags flag = BindingFlags.Default | BindingFlags.Public | BindingFlags.Instance;
if (!OptionCaseSensitiveEvaluationActive)
flag |= BindingFlags.IgnoreCase;
if (OptionAllowNonPublicMembersAccess)
flag |= BindingFlags.NonPublic;
return flag;
}
}
protected virtual BindingFlags StaticBindingFlag
{
get
{
BindingFlags flag = BindingFlags.Default | BindingFlags.Public | BindingFlags.Static;
if (!OptionCaseSensitiveEvaluationActive)
flag |= BindingFlags.IgnoreCase;
if (OptionAllowNonPublicMembersAccess)
flag |= BindingFlags.NonPublic;
return flag;
}
}
#endregion
#region Custom and on the fly evaluation
private object context;
/// <summary>
/// If set, this object is used to use it's fields, properties and methods as global variables and functions
/// </summary>
public object Context
{
get { return context; }
set
{
context = value;
defaultVariables["this"] = context;
}
}
private IDictionary<string, object> variables = new Dictionary<string, object>(StringComparer.Ordinal);
/// <summary>
/// Counts stack initialisations to determine if the expression entry point was reached. In that case the transported exception should be thrown.
/// </summary>
private int evaluationStackCount;
/// <summary>
/// A Dictionary of variable name/value that can be use in expressions and scripts evaluate by the current instance of <see cref="ExpressionEvaluator"/><para/>
/// Warning : Make a copy of the given dictionary to manage casing.
/// </summary>
public IDictionary<string, object> Variables
{
get { return variables; }
set
{
if(OptionVariablesPersistenceCustomComparer)
{
variables = value;
}
else
{
variables = value == null ? new Dictionary<string, object>(StringComparerForCasing) : new Dictionary<string, object>(value, StringComparerForCasing);
}
}
}
/// <summary>
/// Is fired just before a script is evaluate.<para/>
/// Allow to redefine the script to evaluate or to force a result value.
/// </summary>
public event EventHandler<ExpressionEvaluationEventArg> ScriptEvaluating;
/// <summary>
/// Is fired just before to return the script evaluation.<para/>
/// Allow to modify on the fly the result of the evaluation.
/// </summary>
public event EventHandler<ExpressionEvaluationEventArg> ScriptEvaluated;
/// <summary>
/// Is fired just before an expression is evaluate.<para/>
/// Allow to redefine the expression to evaluate or to force a result value.
/// </summary>
public event EventHandler<ExpressionEvaluationEventArg> ExpressionEvaluating;
/// <summary>
/// Is fired just before to return the expression evaluation.<para/>
/// Allow to modify on the fly the result of the evaluation.
/// </summary>
public event EventHandler<ExpressionEvaluationEventArg> ExpressionEvaluated;
/// <summary>
/// Is fired before a variable, field or property resolution.<para/>
/// Allow to define a variable and the corresponding value on the fly.<para/>
/// Allow also to cancel the evaluation of this variable (consider it does'nt exists)
/// </summary>
public event EventHandler<VariablePreEvaluationEventArg> PreEvaluateVariable;
/// <summary>
/// Is fired before a function or method resolution.<para/>
/// Allow to define a function or method and the corresponding value on the fly.<para/>
/// Allow also to cancel the evaluation of this function (consider it does'nt exists)
/// </summary>
public event EventHandler<FunctionPreEvaluationEventArg> PreEvaluateFunction;
/// <summary>
/// Is fired before a indexing resolution.<para/>
/// Allow to define an indexing and the corresponding value on the fly.<para/>
/// Allow also to cancel the evaluation of this indexing (consider it does'nt exists)
/// </summary>
public event EventHandler<IndexingPreEvaluationEventArg> PreEvaluateIndexing;
/// <summary>
/// Is fired if no variable, field or property were found.<para/>
/// Allow to define a variable and the corresponding value on the fly.
/// </summary>
public event EventHandler<VariableEvaluationEventArg> EvaluateVariable;
/// <summary>
/// Is fired if no function or method were found.<para/>
/// Allow to define a function or method and the corresponding value on the fly.
/// </summary>
public event EventHandler<FunctionEvaluationEventArg> EvaluateFunction;
/// <summary>
/// Is fired when a parameter is not of the correct type for the function.<para/>
/// Allow to define a custom parameter cast to make the function call work on the fly.
/// </summary>
public event EventHandler<ParameterCastEvaluationEventArg> EvaluateParameterCast;
#endregion