using System;

using System.Collections.Generic;

​

public class Program

{

    public static void Main()

    {

        var emp = new Employee();

        emp.Addresses.Add("嘉義市大馬路 123 號");

​

        emp.Addresses = new List<string>(); // 編譯失敗：不允許修改。

        //Console.WriteLine(emp.Addresses[0]);

    }

​

    public class Employee

    {

        public List<string> Addresses { get; } // 唯讀自動屬性

​

        public Employee()

        {

            Addresses = new List<string>();

        }

        public void DoSomethingStupid() 

        {

            Addresses = null; // 編譯失敗：不允許修改。

        }

    }

}