How create a new deep copy (clone) of a List<T>?

Question

In the following piece of code,

using System;
using System.Collections.Generic;
using System.Drawing;
using System.Windows.Forms;

namespace clone_test_01
{

    public partial class MainForm : Form
    {

        public class Book
        {
            public string title = "";

            public Book(string title)
            {
                this.title = title;
            }
        }


        public MainForm()
        {
            InitializeComponent();

            List<Book> books_1 = new List<Book>();
            books_1.Add(  new Book("One")  );
            books_1.Add(  new Book("Two")  );
            books_1.Add(  new Book("Three")  );
            books_1.Add(  new Book("Four")  );

            List<Book> books_2 = new List<Book>(books_1);

            books_2[0].title = "Five";
            books_2[1].title = "Six";

            textBox1.Text = books_1[0].title;
            textBox2.Text = books_1[1].title;
        }
    }

}

I use a Book object type to create a List<T> and I populate it with a few items giving them a unique title (from 'one' to 'five').

Then I create List<Book> books_2 = new List<Book>(books_1).

From this point, I know it's a clone of the list object, BUT the book objects from book_2 are still a reference from the book objects in books_1. It's proven by making changes on the two first elements of books_2, and then checking those same elements of book_1 in a TextBox.

books_1[0].title and books_2[1].title have indeed been changed to the new values of books_2[0].title and books_2[1].title.

NOW THE QUESTION

How do we create a new hard copy of a List<T>? The idea is that books_1 and books_2 become completely independent of each other.

I'm disappointed Microsoft didn't offer a neat, fast and easy solution like Ruby are doing with the clone() method.

What would be really awesome from helpers is to use my code and alter it with a workable solution so it can be compiled and work. I think it will truly help newbies trying to understand offered solutions for this issue.

EDIT: Note that the Book class could be more complex and have more properties. I tried to keep things simple.

Answer 1

You need to create new Book objects then put those in a new List:

List<Book> books_2 = books_1.Select(book => new Book(book.title)).ToList();

Update: Slightly simpler... List<T> has a method called ConvertAll that returns a new list:

List<Book> books_2 = books_1.ConvertAll(book => new Book(book.title));