在 Visual Studio 2017（調試版本）中運行以下代碼時，我遇到了一些奇怪的行為：using System;using System.Collections.Generic;namespace ConsoleApp2{    public class Program    {        public static class DefaultCustomers        {            public static readonly Customer NiceCustomer = new Customer() { Name = "Mr. Nice Guy " };            public static readonly Customer EvilCustomer = new Customer() { Name = "Mr. Evil Guy " };            public static readonly Customer BrokeCustomer = new Customer() { Name = "Mr. Broke Guy" };        }        public class Customer        {            public static readonly IEnumerable<Customer> UnwantedCustomers = new[] { DefaultCustomers.EvilCustomer, DefaultCustomers.BrokeCustomer };            public string Name { get; set; }            public override string ToString()            {                return Name;            }        }        public static void Main(string[] args)        {            Console.WriteLine(new Customer() { Name = "Some other customer" });            //Console.WriteLine(DefaultCustomers.NiceCustomer);            foreach (var customer in Customer.UnwantedCustomers)            {                Console.WriteLine(customer != null ? customer.ToString() : "null");            }            Console.ReadLine();        }    }}控制臺上的輸出是Some other customerMr. Evil GuyMr. Broke Guy這大致是我預期的行為。但是，如果我取消注釋 Program.Main(...) 中的第二行，輸出將更改為Some other customerMr. Nice Guynullnull我知道可以通過將 UnwantedCustomers 轉換為靜態只讀屬性來輕松解決此問題。但我想知道所描述的行為是否遵循類和對象的初始化順序，或者這種行為是否未定義？