Esempio n. 1
0
        /// <summary>
        /// Creates constant expression. Main problem is to pick up right type if no recommended provided.
        /// </summary>
        private static Expression CreateConstantExpression(MemberOrConstantToken mcToken, Type recommendedType)
        {
            object obj;

            if (recommendedType != null)
            {
                TypeUtils.ConvertFromString(mcToken.StrValue, recommendedType, out obj);
            }
            else
            {
                do
                {
                    if (TypeUtils.ConvertFromString(mcToken.StrValue, typeof(int), out obj))
                    {
                        break;
                    }
                    if (TypeUtils.ConvertFromString(mcToken.StrValue, typeof(float), out obj))
                    {
                        break;
                    }
                    if (TypeUtils.ConvertFromString(mcToken.StrValue, typeof(bool), out obj))
                    {
                        break;
                    }
                    if (TypeUtils.ConvertFromString(mcToken.StrValue, typeof(DateTime), out obj))
                    {
                        break;
                    }
                    if (TypeUtils.ConvertFromString(mcToken.StrValue, typeof(string), out obj))
                    {
                        break;
                    }
                }while (false);
            }

            Expression result = recommendedType == null?Expression.Constant(obj) : Expression.Constant(obj, recommendedType);

            return(result);
        }
Esempio n. 2
0
        /// <summary>
        /// Builds expressions related to Property extraction, Function call, Type conversion and Constants
        /// </summary>
        /// <param name="tokens">Tokens list</param>
        /// <param name="contexts">List of ParameterExpressions - variables which will be passed as Funtor's arguments</param>
        /// <param name="recommendedType">If not null, tryes to convert resulted type of expression to recommendedType (no 100% guarantee)</param>
        /// <returns>Expression</returns>
        private static Expression BuildMembersExpression(ListSegment <Token> tokens, List <Expression> contexts, Type recommendedType)
        {
            int                   state           = 0; //0-separator, 1-expression, 2-function
            Expression            result          = contexts[0];
            MemberOrConstantToken methodToken     = null;
            MemberOrConstantToken conversionToken = null;

            for (int i = 0; i < tokens.Count; ++i)
            {
                switch (state)
                {
                case 0:
                {
                    MemberOrConstantToken mcToken = tokens[i] as MemberOrConstantToken;
                    if (mcToken != null)
                    {
                        if (mcToken.IsString)
                        {
                            if (i == 0)
                            {
                                result = Expression.Constant(mcToken.StrValue);
                            }
                            else
                            {
                                throw new BuilderException(mcToken.Position, BuilderException.BuilderExceptionType.UnexpectedConstant, mcToken.StrValue);
                            }
                        }
                        else if (i == tokens.Count - 1 || tokens[i + 1] is PointToken)
                        {
                            if (i == 0 && mcToken.StrValue.Length > 2 && mcToken.StrValue.Substring(0, 3).ToLower() == "arg")
                            {
                                string numstr = mcToken.StrValue.Substring(3);
                                if (numstr != string.Empty)
                                {
                                    int num = 0;
                                    try { num = Convert.ToInt32(numstr); }
                                    catch { throw new BuilderException(mcToken.Position, BuilderException.BuilderExceptionType.WrongArgFormat); }
                                    if (num >= contexts.Count)
                                    {
                                        throw new BuilderException(mcToken.Position, BuilderException.BuilderExceptionType.ArgNumberExceedsMax);
                                    }
                                    result = contexts[num];
                                }
                            }
                            else
                            {
                                PropertyInfo pi = TypeUtils.GetPropertyInfo(result.Type, mcToken.StrValue);
                                if (pi != null)
                                {
                                    result = Expression.Property(result, pi);
                                }
                                else if (i == 0)
                                {
                                    result = CreateConstantExpression(mcToken, tokens.Count == 1 ? recommendedType : null);
                                }
                                else
                                {
                                    throw new BuilderException(mcToken.Position, BuilderException.BuilderExceptionType.PropertyNotExists, pi.Name);
                                }
                            }
                        }
                        else
                        {
                            if (i == 0 && mcToken.IsConversion)
                            {
                                conversionToken = mcToken;
                                state           = 2;
                            }
                            else
                            {
                                if (TypeUtils.MethodExists(result.Type, mcToken.StrValue))
                                {
                                    state = 2; methodToken = mcToken;
                                }
                                else if (i == 0)
                                {
                                    result = CreateConstantExpression(mcToken, tokens.Count == 1 ? recommendedType : null);
                                }
                                else
                                {
                                    throw new BuilderException(mcToken.Position, BuilderException.BuilderExceptionType.FunctionNotExists, mcToken.StrValue);
                                }
                            }
                        }
                        if (state == 0)
                        {
                            state = 1;
                        }
                        break;
                    }

                    BracketsToken brToken = tokens[i] as BracketsToken;
                    if (brToken != null)
                    {
                        result = BuildExpression(new ListSegment <Token>(brToken.Tokens), contexts, null);
                        state  = 1;
                        break;
                    }

                    throw new BuilderException(tokens[i].Position, BuilderException.BuilderExceptionType.IncorrectExpression);
                }

                case 1:
                    if (tokens[i] is PointToken)
                    {
                        state = 0;
                    }
                    else
                    {
                        throw new BuilderException(tokens[i].Position, BuilderException.BuilderExceptionType.UnexpectedExpression);
                    }
                    break;

                case 2:
                {
                    BracketsToken brToken = tokens[i] as BracketsToken;
                    if (brToken != null)
                    {
                        int argsCount = GetParamsNumber(brToken);

                        if (methodToken != null)
                        {
                            MethodInfo mi = TypeUtils.GetMethodInfo(result.Type, methodToken.StrValue, 0);
                            if (mi == null)
                            {
                                throw new BuilderException(methodToken.Position, BuilderException.BuilderExceptionType.NoFunctionFound);
                            }
                            if (argsCount == 0)
                            {
                                result = Expression.Call(result, mi);
                            }
                            else
                            {
                                ParameterInfo[] pinfos           = mi.GetParameters();
                                List <Type>     recommendedTypes = new List <Type>();

                                for (int j = 0; j < pinfos.Length; ++j)
                                {
                                    if (!pinfos[j].IsOut && !pinfos[j].IsRetval)
                                    {
                                        recommendedTypes.Add(pinfos[j].ParameterType);
                                    }
                                    else
                                    {
                                        throw new BuilderException(tokens[i].Position, BuilderException.BuilderExceptionType.ParameterTypeNotSupported, pinfos[j].Name);
                                    }
                                }

                                List <Expression> args = BuildFunctionArgumentsList(brToken, contexts, recommendedTypes);
                                result = Expression.Call(result, mi, args);
                            }
                        }
                        else if (conversionToken != null)
                        {
                            if (argsCount != 1)
                            {
                                throw new BuilderException(conversionToken.Position, BuilderException.BuilderExceptionType.WrongArgumentsNumber, "1 expected");
                            }

                            List <Type> recommendedTypes = new List <Type>();
                            recommendedTypes.Add(null);

                            List <Expression> args = BuildFunctionArgumentsList(brToken, contexts, recommendedTypes);
                            result = conversionToken.CreateConversion(args[0]);
                        }
                        else
                        {
                            throw new BuilderException(brToken.Position, BuilderException.BuilderExceptionType.UnexpectedError);
                        }

                        methodToken     = null;
                        conversionToken = null;
                        state           = 1;
                    }
                    else
                    {
                        throw new BuilderException(tokens[i].Position, BuilderException.BuilderExceptionType.FunctionArgumentsExpected);
                    }
                }
                break;
                }
            }

            if (state == 2)
            {
                throw new BuilderException(tokens[tokens.Count - 1].Position, BuilderException.BuilderExceptionType.FunctionArgumentsExpected);
            }

            return(result);
        }