Add support to change the current CulutureInfo

Sieve/Models/SieveOptions.cs

@@ -1,4 +1,4 @@
-namespace Sieve.Models
+namespace Sieve.Models
 {
     public class SieveOptions
     {
@@ -13,5 +13,7 @@ public class SieveOptions
         public bool IgnoreNullsOnNotEqual { get; set; } = true;
 
         public bool DisableNullableTypeExpressionForSorting { get; set; } = false;
+
+        public string CultureNameOfTypeConversion { get; set; } = "en";
     }
 }

Sieve/Services/SieveProcessor.cs

@@ -1,6 +1,7 @@
 using System;
 using System.Collections.Generic;
 using System.ComponentModel;
+using System.Globalization;
 using System.Linq;
 using System.Linq.Expressions;
 using System.Reflection;
@@ -172,6 +173,8 @@ protected virtual IQueryable<TEntity> ApplyFiltering<TEntity>(TSieveModel model,
                 return result;
             }
 
+            var cultureInfoToUseForTypeConversion = new CultureInfo(Options.Value.CultureNameOfTypeConversion ?? "en");
+
             Expression outerExpression = null;
             var parameter = Expression.Parameter(typeof(TEntity), "e");
             foreach (var filterTerm in model.GetFiltersParsed())
@@ -198,7 +201,7 @@ protected virtual IQueryable<TEntity> ApplyFiltering<TEntity>(TSieveModel model,
 
                             var filterValue = isFilterTermValueNull
                                 ? Expression.Constant(null, property.PropertyType)
-                                : ConvertStringValueToConstantExpression(filterTermValue, property, converter);
+                                : ConvertStringValueToConstantExpression(filterTermValue, property, converter, cultureInfoToUseForTypeConversion);
 
                             if (filterTerm.OperatorIsCaseInsensitive && !isFilterTermValueNull)
                             {
@@ -309,15 +312,14 @@ private static Expression GenerateFilterNullCheckExpression(Expression propertyV
                     Expression.NotEqual(propertyValue, Expression.Default(propertyValue.Type)));
         }
 
-        private static Expression ConvertStringValueToConstantExpression(string value, PropertyInfo property,
-            TypeConverter converter)
+        private static Expression ConvertStringValueToConstantExpression(string value, PropertyInfo property, TypeConverter converter, CultureInfo cultureInfo)
         {
             // to allow user to distinguish between prop==null (as null) and prop==\null (as "null"-string)
             value = value.Equals(EscapeChar + NullFilterValue, StringComparison.InvariantCultureIgnoreCase) 
                 ? value.TrimStart(EscapeChar) 
                 : value;
             dynamic constantVal = converter.CanConvertFrom(typeof(string))
-                ? converter.ConvertFrom(value)
+                ? converter.ConvertFrom(null, cultureInfo, value)
                 : Convert.ChangeType(value, property.PropertyType);
 
             return GetClosureOverConstant(constantVal, property.PropertyType);

SieveUnitTests/Abstractions/Entity/IPost.cs

@@ -9,6 +9,8 @@ public interface IPost: IBaseEntity
         string Title { get; set; }
         [Sieve(CanFilter = true, CanSort = true)]
         int LikeCount { get; set; }
+        [Sieve(CanFilter = true)]
+        float MeanRating { get; set; }
         [Sieve(CanFilter = true, CanSort = true)]
         int CommentCount { get; set; }
         [Sieve(CanFilter = true, CanSort = true)]

SieveUnitTests/Entities/Post.cs

@@ -12,6 +12,9 @@ public class Post : BaseEntity, IPost
 
         [Sieve(CanFilter = true, CanSort = true)]
         public int LikeCount { get; set; } = new Random().Next(0, 1000);
+
+        [Sieve(CanFilter = true)]
+        public float MeanRating { get; set; }
 
         [Sieve(CanFilter = true, CanSort = true)]
         public int CommentCount { get; set; } = new Random().Next(0, 1000);

SieveUnitTests/General.cs

@@ -40,6 +40,7 @@ public General(ITestOutputHelper testOutputHelper)
                     Id = 0,
                     Title = "A",
                     LikeCount = 100,
+                    MeanRating = 3.5f,
                     IsDraft = true,
                     CategoryId = null,
                     TopComment = new Comment { Id = 0, Text = "A1" },
@@ -50,6 +51,7 @@ public General(ITestOutputHelper testOutputHelper)
                     Id = 1,
                     Title = "B",
                     LikeCount = 50,
+                    MeanRating = 3.5f,
                     IsDraft = false,
                     CategoryId = 1,
                     TopComment = new Comment { Id = 3, Text = "B1" },
@@ -60,6 +62,7 @@ public General(ITestOutputHelper testOutputHelper)
                     Id = 2,
                     Title = "C",
                     LikeCount = 0,
+                    MeanRating = 3.5f,
                     CategoryId = 1,
                     TopComment = new Comment { Id = 2, Text = "C1" },
                     FeaturedComment = new Comment { Id = 6, Text = "C2" }
@@ -69,6 +72,7 @@ public General(ITestOutputHelper testOutputHelper)
                     Id = 3,
                     Title = "D",
                     LikeCount = 3,
+                    MeanRating = 3.5f,
                     IsDraft = true,
                     CategoryId = 2,
                     TopComment = new Comment { Id = 1, Text = "D1" },
@@ -79,6 +83,7 @@ public General(ITestOutputHelper testOutputHelper)
                     Id = 4,
                     Title = "Yen",
                     LikeCount = 5,
+                    MeanRating = 3.5f,
                     IsDraft = true,
                     CategoryId = 5,
                     TopComment = new Comment { Id = 4, Text = "Yen3" },
@@ -848,5 +853,76 @@ public void CanFilterWithEscapedOperators(string filter)
             Assert.Equal(1, resultCount);
         }
 
+        [Theory]
+        [InlineData("en-US", "1.2")]
+        [InlineData("de-DE", @"1\,2")]
+        public void ParseFloatsWithChangedCultureInfo_Works(string culture, string value)
+        {
+            // ARRANGE
+            var posts = new List<Post>
+            {
+                new Post
+                {
+                    Id = 1,
+                    Title = "E\\",
+                    LikeCount = 4,
+                    MeanRating = 1.2f,
+                    IsDraft = true,
+                    CategoryId = 1,
+                    TopComment = new Comment { Id = 1, Text = "E1" },
+                    FeaturedComment = new Comment { Id = 7, Text = "E2" }
+                }
+            }.AsQueryable();
+
+            var optionsAccessor = new SieveOptionsAccessor();
+            optionsAccessor.Value.CultureNameOfTypeConversion = culture;
+
+            var processor = new ApplicationSieveProcessor(optionsAccessor,
+                new SieveCustomSortMethods(),
+                new SieveCustomFilterMethods());
+
+            var model = new SieveModel() { Filters = $"MeanRating=={value}" };
+
+            // ACT
+            var result = processor.Apply(model, posts);
+
+            // ASSERT
+            Assert.NotNull(result);
+        }
+
+        [Theory]
+        [InlineData("en", @"1\,2")]
+        [InlineData("de", "1.2")]
+        public void ParseFloatsWithChangedCultureInfo_Fails(string culture, string value)
+        {
+            // ARRANGE
+            var posts = new List<Post>
+            {
+                new Post
+                {
+                    Id = 1,
+                    Title = "E\\",
+                    LikeCount = 4,
+                    MeanRating = 1.9f,
+                    IsDraft = true,
+                    CategoryId = 1,
+                    TopComment = new Comment { Id = 1, Text = "E1" },
+                    FeaturedComment = new Comment { Id = 7, Text = "E2" }
+                }
+            }.AsQueryable();
+
+            var optionsAccessor = new SieveOptionsAccessor();
+            optionsAccessor.Value.CultureNameOfTypeConversion = culture;
+
+            var processor = new ApplicationSieveProcessor(optionsAccessor,
+                new SieveCustomSortMethods(),
+                new SieveCustomFilterMethods());
+
+            var model = new SieveModel() { Filters = $"MeanRating=={value}" };
+
+            // ACT, ASSERT
+            Assert.Throws<SieveException>(() => processor.Apply(model, posts));
+        }
+
     }
 }