using System;

using System.Linq;                  

using System.Collections.Generic;

using System.Linq.Expressions;

​

public class Program

{

    public class MyKVP

    {

        public int ID {get;set;}

        public string Name {get;set;}

    }

    private static List<MyKVP> list = new List<MyKVP>{

        new MyKVP{ID = 1, Name = "test1"},

        new MyKVP{ID = 1, Name = "test1"},

        new MyKVP{ID = 2, Name = "test2"},

        new MyKVP{ID = 2, Name = "test2"},

        new MyKVP{ID = 3, Name = "test3"}

    };

    public static void Main()

    {

        //var x = list.GroupBy(z => z.ID).Select(g => g.First());

        var x = list.Distinct(z => z.ID);

        foreach(var y in x){

        Console.WriteLine(y.Name);

        }       

    }

}

​

internal static class EFExtensions

{

    public static IEnumerable<T> Distinct<T>(this IEnumerable<T> source, Expression<Func<T, object>> prop)

    {

        return source.GroupBy(prop.Compile()).Select(g => g.First());

    }

}