using System;

using System.Linq;

using System.Collections.Generic;

​

public class DealResponse

{

    public int detailId { get; set; }

    public string detailcd { get; set; }

    public string fileName { get; set; }

    public int isNgo { get; set; }

    public override string ToString()

    {

        return string.Format("id: {0} cd: {1} fileName: {2} isNgo: {3}", detailId, detailcd, fileName, isNgo);

    }

}

​

public class DealResponseComprarer : IEqualityComparer<DealResponse>

{

    public bool Equals(DealResponse x, DealResponse y)

    {

        return x.detailId == y.detailId &&  x.detailcd == y.detailcd ;

    }

​

    public int GetHashCode(DealResponse obj)

    {

        return (obj.detailId.GetHashCode() + obj.detailcd.GetHashCode());

    }

}

​

public class Program

{

    public static void Main()

    {

        var L1 = new List<DealResponse>

        {

            new DealResponse { detailId = 5, detailcd = "ABC" , fileName = "string 1", isNgo = 0 },

            new DealResponse { detailId = 5, detailcd = "DEF" , fileName = "string 2", isNgo = 0 }, 

            new DealResponse { detailId = 5, detailcd = "XYZ" , fileName = "string ",  isNgo = 0 }

        };

        var L2 = new List<DealResponse> 

        {

            new DealResponse { detailId = 5, detailcd = "ABC" , fileName = "string 11", isNgo = 1 },

            new DealResponse { detailId = 6, detailcd = "MNO" , fileName = "string 3",  isNgo = 1 }  

        };

        var combined = L2.Concat(L1.Except(L2, new DealResponseComprarer()));

        foreach (var c in combined)

        {

            Console.WriteLine(c);

        }

    }

}