1. Change the property "Group" of DataSourceResult to "Groups".

2. Add new property "Aggregate" to DataSourceRequest.
3. Fixed getting wrong grouping data in the request using aggregates in grouping configuration.

Author: JftCoCo

.vscode/launch.json

@@ -5,7 +5,7 @@
    "version": "0.2.0",
    "configurations": [
         {
-            "name": ".NET Core Launch (console)",
+            "name": ".NET Core Launch 1.0(console)",
             "type": "coreclr",
             "request": "launch",
             "preLaunchTask": "build",
@@ -16,7 +16,33 @@
             // For more information about the 'console' field, see https://github.com/OmniSharp/omnisharp-vscode/blob/master/debugger-launchjson.md#console-terminal-window
             "console": "internalConsole",
             "stopAtEntry": false,
-            "internalConsoleOptions": "openOnSessionStart"
+            "internalConsoleOptions": "openOnSessionStart",
+            "logging": {
+                "engineLogging": false,
+                "moduleLoad": false,
+                "exceptions": true,
+                "browserStdOut": false
+            }
+        },
+        {
+            "name": ".NET Core Launch 2.0(console)",
+            "type": "coreclr",
+            "request": "launch",
+            "preLaunchTask": "build",
+            // If you have changed target frameworks, make sure to update the program path.
+            "program": "${workspaceFolder}/src/Kendo.DynamicLinqCore.Test/bin/Debug/netcoreapp2.1/Kendo.DynamicLinqCore.Test.dll",
+            "args": [],
+            "cwd": "${workspaceFolder}/src/Kendo.DynamicLinqCore.Test",
+            // For more information about the 'console' field, see https://github.com/OmniSharp/omnisharp-vscode/blob/master/debugger-launchjson.md#console-terminal-window
+            "console": "internalConsole",
+            "stopAtEntry": false,
+            "internalConsoleOptions": "openOnSessionStart",
+            "logging": {
+                "engineLogging": false,
+                "moduleLoad": false,
+                "exceptions": true,
+                "browserStdOut": false
+            }
         },
         {
             "name": ".NET Core Attach",

README.md

@@ -4,7 +4,7 @@
 [![Downloads](https://img.shields.io/nuget/dt/Kendo.DynamicLinqCore.svg)](https://www.nuget.org/packages/Kendo.DynamicLinqCore)
 
 ## Description
-Kendo.DynamicLinqCore implements server paging, filtering, sorting and aggregating to Kendo UI via Dynamic Linq for .Net Core App(1.x ~ 2.x).
+Kendo.DynamicLinqCore implements server paging, filtering, sorting, grouping and aggregating to Kendo UI via Dynamic Linq for .Net Core App(1.x ~ 2.x).
 
 ## Usage
 1. Add the Kendo.DynamicLinqCore NuGet package to your project.
@@ -22,7 +22,7 @@ schema: {
     data: "Data",
     total: "Total",
     aggregates: "Aggregates",
-    groups: "Group",
+    groups: "Groups",
     errors: "Errors"
 }
 ```  
@@ -37,7 +37,7 @@ dataSource: {
         data: "Data",
         total: "Total",
         aggregates: "Aggregates",
-        groups: "Group",
+        groups: "Groups",
         errors: "Errors",
         ...
     },
@@ -72,12 +72,12 @@ dataSource: {
 ..... Other kendo grid code .....
 ```
 5. Import the Kendo.DynamicLinqCore namespace.
-6. Use the `ToDataSourceResult` extension method to apply paging, sorting and filtering
+6. Use the `ToDataSourceResult` extension method to apply paging, sorting, filtering, grouping and aggregating.
 ```c#
 using Kendo.DynamicLinqCore
 
 [WebMethod]
-public static DataSourceResult Products(int take, int skip, IEnumerable<Sort> sort, Filter filter, IEnumerable<Aggregator> aggregates, IEnumerable<Sort> group)
+public static DataSourceResult Products(int take, int skip, IEnumerable<Sort> sort, Filter filter, IEnumerable<Aggregator> aggregates, IEnumerable<Group> groups)
 {
     using (var northwind = new Northwind())
     {
@@ -91,7 +91,7 @@ public static DataSourceResult Products(int take, int skip, IEnumerable<Sort> so
                    UnitsInStock = p.UnitsInStock,
                    Discontinued = p.Discontinued
                })
-               .ToDataSourceResult(take, skip, sort, filter, aggregates, group);
+               .ToDataSourceResult(take, skip, sort, filter, aggregates, groups);
     }
 }
 ```
@@ -114,7 +114,7 @@ public IActionResult Products([FromBody] DataSourceRequest requestModel)
                    UnitsInStock = p.UnitsInStock,
                    Discontinued = p.Discontinued
                })
-               .ToDataSourceResult(requestModel.Take, requestModel.Skip, requestModel.Sort, requestModel.Filter);
+               .ToDataSourceResult(requestModel.Take, requestModel.Skip, requestModel.Sort, requestModel.Filter, requestModel.Aggregate, requestModel.Group);
     }
 }
 ```
@@ -143,17 +143,14 @@ public class MyContext : DbContext
 4. Run "dotnet pack --configuration Release"
 
 ## Note
-Kendo.DynamicLinqCore is referred to Kendo.DynamicLinq by [kendo-labs](https://github.com/kendo-labs/dlinq-helpers). Related notes can refer it.
+Kendo.DynamicLinqCore is referred to Kendo.DynamicLinq by [Ali Sarkis](https://github.com/mshtawythug/dlinq-helpers).
 
-## Examples
-The following examples use Kendo.DynamicLinq(Not Kendo.DynamicLinqCore, but similar) and you can consult.
+## Kendo UI Documentation
+The following links are Kendo UI online docs(related to this package) and you can refer to.
 
-- [ASP.NET MVC](https://github.com/telerik/kendo-examples-asp-net-mvc/tree/master/grid-crud)
-- [ASP.NET Web Forms and Page Methods](https://github.com/telerik/kendo-examples-asp-net/tree/master/grid-page-methods-crud)
-- [ASP.NET Web Forms and WCF](https://github.com/telerik/kendo-examples-asp-net/tree/master/grid-wcf-crud)
-- [ASP.NET Web Forms and Web Services](https://github.com/telerik/kendo-examples-asp-net/tree/master/grid-web-service-crud)
-- [ASP.NET Web Forms and Web API](https://github.com/telerik/kendo-examples-asp-net/tree/master/grid-webapi-crud)
+- [Kendo UI Grid](https://docs.telerik.com/kendo-ui/api/javascript/ui/grid)
+- [Kendo DataSource](https://docs.telerik.com/kendo-ui/api/javascript/data/datasource)
 
-More Kendo UI Grid configuration can refer to [here](https://demos.telerik.com/kendo-ui/) 
+More Kendo UI configuration can refer to [here](https://demos.telerik.com/kendo-ui/)
 
 

src/Kendo.DynamicLinqCore.Test/Kendo.DynamicLinqCore.Test.csproj

@@ -2,9 +2,13 @@
 
   <PropertyGroup>
     <OutputType>Exe</OutputType>
-    <TargetFramework>netcoreapp1.0</TargetFramework>
+    <TargetFrameworks>netcoreapp1.0;netcoreapp2.1</TargetFrameworks>
   </PropertyGroup>
 
+  <ItemGroup Condition="'$(TargetFramework)'=='netcoreapp1.0'"></ItemGroup>
+
+  <ItemGroup Condition="'$(TargetFramework)'=='netcoreapp2.1'"></ItemGroup>
+
   <ItemGroup>
     <ProjectReference Include="../Kendo.DynamicLinqCore/Kendo.DynamicLinqCore.csproj" />
   </ItemGroup>

src/Kendo.DynamicLinqCore.Test/Program.cs

@@ -12,57 +12,70 @@ class Program
                 Identification = Guid.Parse("F057D609-F1F3-4E5C-BC09-0AC0BBE1007D"),
                 Name = "Monie",
                 Introduce = "I'm Monie",
-                Salary = 1000000,
+                Salary = 1000,
                 EmployeeNumber = 10,
                 Birthday = new DateTime(2000,5,5) 
             }, 
             new Person { 
                 Identification = Guid.Parse("F586A608-4095-4E8E-8F21-AEFC0DFDB61F"),
                 Name = "CoCo",
                 Introduce = "I'm CoCo",
-                Salary = 2500000,
+                Salary = 2500,
                 EmployeeNumber = 77,
                 Birthday = new DateTime(1986,10,10) 
             },
             new Person { 
                 Identification = Guid.Parse("F4FFE20C-4DE5-4DC5-9686-955FB74EE05E"),
                 Name = "Kirin",
-                Salary = 3000000,
+                Salary = 3000,
                 EmployeeNumber = 66,
                 Birthday = new DateTime(1984,7,8) 
             },
             new Person { 
                 Identification = Guid.Parse("CCAB16DB-070B-4A93-846A-81AEEFDD42EE"),
                 Name = "Rock",
                 Introduce = "",
-                Salary = 1750000,
+                Salary = 1750,
                 EmployeeNumber = 35,
                 Birthday = new DateTime(1976,11,6) 
             },
             new Person { 
                 Identification = null,
                 Name = "Pikachu",
                 Introduce = "Pika~ Pika~",
-                Salary = 66000,
+                Salary = 6600,
                 EmployeeNumber = 18,
                 Birthday = new DateTime(2005,3,16) 
             }
         };
 
         static void Main(string[] args)
-        {            
+        {    
+            #if NETCOREAPP1_0 || NETCOREAPP1_1
+                Console.WriteLine("/---------- Net Core App 1.x ----------/");
+            #else
+                Console.WriteLine("/---------- Net Core App 2.x ----------/");
+            #endif
+
+            Console.WriteLine("----------------------------------------");
+
             /* Test 1 */
             var result = people.AsQueryable().ToDataSourceResult(1, 2, null, null, new[]
             {
                 new Aggregator
                 {
                     Aggregate = "sum",
                     Field = "Salary"
+                },
+                new Aggregator
+                {
+                    Aggregate = "average",
+                    Field = "Salary"
                 }
             }, null);
 
-            Console.WriteLine("/********** Test 1 **********/");
-            Console.WriteLine(result.Aggregates);
+            Console.WriteLine("\r\n/********** Test 1 **********/");
+            Console.WriteLine(result.Aggregates);   // { Salary = { sum = 14850, average = 2970 } }
 
 
             /* Test 2 */
@@ -79,10 +92,10 @@ static void Main(string[] args)
                 Logic = "and"
             }, null, null);
 
-            Console.WriteLine("/********** Test 2 **********/");
+            Console.WriteLine("\r\n/********** Test 2 **********/");
             foreach (var p in result.Data)
             {
-                Console.WriteLine((p as Person).Name);
+                Console.WriteLine((p as Person).Name);  // Kirin, Rock
             }
 
 
@@ -115,10 +128,10 @@ static void Main(string[] args)
                 Logic = "and"
             }, null, null);
 
-            Console.WriteLine("/********** Test 3 **********/");
+            Console.WriteLine("\r\n/********** Test 3 **********/");
             foreach (var p in result.Data)
             {
-                Console.WriteLine((p as Person).Name);
+                Console.WriteLine((p as Person).Name);  // CoCo, Monie
             }
 
             Console.ReadKey();

src/Kendo.DynamicLinqCore/Aggregator.cs

@@ -1,5 +1,4 @@
 using System;
-using System.Globalization;
 using System.Linq;
 using System.Linq.Expressions;
 using System.Reflection;

src/Kendo.DynamicLinqCore/DataSourceRequest.cs

@@ -28,5 +28,10 @@ public class DataSourceRequest
         /// Specifies the requested grouping .
         /// </summary>
         public IEnumerable<Group> Group { get; set; }
+
+        /// <summary>
+        /// Specifies the requested aggregators.
+        /// </summary>
+        public IEnumerable<Aggregator> Aggregate { get; set; }
     }
 }

src/Kendo.DynamicLinqCore/DataSourceResult.cs

@@ -20,17 +20,17 @@ public class DataSourceResult
         /// <summary>
         /// Represents a single page of processed grouped data.
         /// </summary>
-        public IEnumerable Group { get; set; }
+        public IEnumerable Groups { get; set; }
 
         /// <summary>
-        /// The total number of records available.
+        /// Represents a requested aggregates.
         /// </summary>
-        public int Total { get; set; }
+        public object Aggregates { get; set; }
 
         /// <summary>
-        /// Represents a requested aggregates.
+        /// The total number of records available.
         /// </summary>
-        public object Aggregates { get; set; }
+        public int Total { get; set; }
 
         /// <summary>
         /// Represents error information from server-side.

src/Kendo.DynamicLinqCore/EnumerableExtensions.cs

@@ -2,6 +2,8 @@
 using System.Collections.Generic;
 using System.Linq;
 using System.Linq.Dynamic.Core;
+using System.Linq.Expressions;
+using System.Reflection;
 
 namespace Kendo.DynamicLinqCore
 {
@@ -14,7 +16,9 @@ public static dynamic GroupByMany<TElement>(this IEnumerable<TElement> elements,
             foreach (var selector in groupSelectors)
             {
                 //compile the Dynamic Expression Lambda for each one
+                //var expression = DynamicExpressionParser.ParseLambda(typeof(TElement), typeof(object), selector.Field);
                 var expression = DynamicExpressionParser.ParseLambda(false, typeof(TElement), typeof(object), selector.Field);
+                
                 //add it to the list
                 selectors.Add(new GroupSelector<TElement>
                 {
@@ -41,7 +45,7 @@ public static dynamic GroupByMany<TElement>(this IEnumerable<TElement> elements,
                             g => new GroupResult
                             {
                                 Value = g.Key,
-                                Aggregates = selector.Aggregates,
+                                Aggregates = Aggregates(g.AsQueryable(),selector.Aggregates),
                                 HasSubgroups = groupSelectors.Length > 1,
                                 Count = g.Count(),                                
                                 Items = g.GroupByMany(nextSelectors),   //recursivly group the next selectors
@@ -52,6 +56,57 @@ public static dynamic GroupByMany<TElement>(this IEnumerable<TElement> elements,
             //if there are not more group selectors return data
             return elements;
         }
+
+        private static object Aggregates<T>(IQueryable<T> queryable, IEnumerable<Aggregator> aggregates)
+        {
+            if (aggregates != null && aggregates.Any())
+            {
+                var objProps = new Dictionary<DynamicProperty, object>();
+                var groups = aggregates.GroupBy(g => g.Field);
+                Type type = null;
+
+                foreach (var group in groups)
+                {
+                    var fieldProps = new Dictionary<DynamicProperty, object>();
+                    foreach (var aggregate in group)
+                    {
+                        var prop = typeof(T).GetProperty(aggregate.Field);
+                        var param = Expression.Parameter(typeof(T), "s");
+                        var selector = aggregate.Aggregate == "count" && (Nullable.GetUnderlyingType(prop.PropertyType) != null)
+                            ? Expression.Lambda(Expression.NotEqual(Expression.MakeMemberAccess(param, prop), Expression.Constant(null, prop.PropertyType)), param)
+                            : Expression.Lambda(Expression.MakeMemberAccess(param, prop), param);
+                        var mi = aggregate.MethodInfo(typeof(T));
+                        if (mi == null) continue;
+
+                        var val = queryable.Provider.Execute(Expression.Call(null, mi, aggregate.Aggregate == "count" && (Nullable.GetUnderlyingType(prop.PropertyType) == null)
+                                  ? new[] { queryable.Expression }
+                                  : new[] { queryable.Expression, Expression.Quote(selector) }));
+
+                        fieldProps.Add(new DynamicProperty(aggregate.Aggregate, typeof(object)), val);                        
+                    }
+                    
+                    type = DynamicClassFactory.CreateType(fieldProps.Keys.ToList());
+                    var fieldObj = Activator.CreateInstance(type);
+                    foreach (var p in fieldProps.Keys)
+                    {
+                        type.GetProperty(p.Name).SetValue(fieldObj, fieldProps[p], null);
+                    }
+                    objProps.Add(new DynamicProperty(group.Key, fieldObj.GetType()), fieldObj);
+                }
+
+                type = DynamicClassFactory.CreateType(objProps.Keys.ToList());
+
+                var obj = Activator.CreateInstance(type);
+                foreach (var p in objProps.Keys)
+                {
+                    type.GetProperty(p.Name).SetValue(obj, objProps[p], null);
+                }
+
+                return obj;
+            }
+            
+            return null;
+        }
 
         public static IEnumerable<T> Append<T>(this IEnumerable<T> source, T item)
         {