using System;

using System.Collections.Generic;

using System.Linq;

using ext;

public class Program

{

    public static void Main()

    {

        myclass2 tmpMyClass2_1=new myclass2();

        tmpMyClass2_1.str1="2-1-1";

        tmpMyClass2_1.str2="";

        myclass2 tmpMyClass2_2=new myclass2();

        tmpMyClass2_2.str1="2-2-1";

        tmpMyClass2_2.str2="";

        List<myclass2> tmpMyClass2List=new List<myclass2>();

        tmpMyClass2List.Add(tmpMyClass2_1);

        tmpMyClass2List.Add(tmpMyClass2_2);

        myclass1 myobj1=new myclass1();

        myclass1 myobj2=new myclass1();

​

        myobj1.list=new List<myclass2>(tmpMyClass2List.Clone());

        myobj2.list=new List<myclass2>(tmpMyClass2List.Clone());

        myobj1.list[0].str2="123";

        myobj2.list[0].str2="456";

​

        Console.WriteLine(myobj1.list[0].str2);

        Console.WriteLine(myobj2.list[0].str2);

​

    }

}

namespace ext{

public static class extclass

{

    public static IList<T> Clone<T>(this IList<T> listToClone) where T:ICloneable

    {

        return listToClone.Select(item => (T)item.Clone()).ToList();

    }

}

}

public class myclass1

{

    public List<myclass2> list {get;set;}

    public myclass1()

    {

        this.list=new List<myclass2>();

    }

​

​

}

​

public class myclass2:System.ICloneable

{

    public string str1 {get;set;}

    public string str2 {get;set;}

    public object Clone()

    {

        return  this.MemberwiseClone();

    }

}