LINQ to Datatable Group by and return all columns

c#, linq

Solution

var _result =   from r1 in dtResults.AsEnumerable()
                group r1 by new
                {
                    ID = r1.Field<int>("ID"),
                    Age = r1.Field<int>("Age"),
                    LastName =  r1.Field<int>("LastName"),
                    FirstName = r1.Field<int>("FirstName"),
                    Sex =  r1.Field<int>("Sex"),
                    Class =  r1.Field<int>("class"),
                    Father_Name =  r1.Field<int>("Father_Name"),
                    Mother_Name =  r1.Field<int>("Mother_Name")
                } into g
                select new
                {
                    ID = g.Key.ID,
                    Age = g.Key.Age,
                    LastName =  g.Key.LastName,
                    FirstName = g.Key.FirstName,
                    Sex =  g.Key.Sex,
                    Class =  g.Key.Class,
                    Father_Name =  g.Key.Father_Name,
                    Mother_Name =  g.Key.Mother_Name,
                    TotalMark = g.Sum(x => x.Field<int>("Marks"))
                };

Problem

I have a Datatable ``` ID Age Last name First Name Sex class Father_Name Mother_Name Marks 1 20 A B M 1 A B 50 1 20 A B M 1 A B 50 1 20 A B M 1 A B 100 2 15 F G F 2 H J 40 2 15 F G F 2 H J 50 ``` & I want following results after applying Linq Group by ``` 1 20 A B M 1 A B 200 2 15 F G F 2 H J 90 ``` I am able to get the sum but i am not able to get the other columns in LINQ group by Can anyone help on this ``` var drResults = from r1 in dtResults.AsEnumerable() group r1 by new { MarksSum= r1.Field<int>("Marks"), } into g select new { Total = g.Sum(r1=>r1.Field<int>("Marks")) }; ```

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