using System;

using System.Collections.Generic;

using System.Linq;

public class Program

{

    public static void Main()

    {

        var dtos = new List<DTO> {

            new DTO {First = "Kalpesh", Last = "Shah", Exp = 10},

            new DTO {First = "Rajiv", Last = "Pal", Exp = 10},

            new DTO {First = "Kalpesh", Last = "Shah", Exp = 10},

            new DTO {First = "Rajiv", Last = "Shah", Exp = 10}

        };

        Console.WriteLine(dtos.Count);

        var g = dtos.GroupBy(d => d.First + "," + d.Last);

        foreach(var d in g)

        {

            Console.WriteLine(d.Key + "," + d.First().Exp);

        }

    }

}

​

public class DTO

{

    public string First {get; set;}

    public string Last {get; set;}

    public int Exp {get; set;}

}