C#构造函数传入不同参数实例化对象返回重复属性值问题求助

问题原因 #

• 第一：OriginModel中定义了静态字段_CharacterOrigin，静态字段属于类全局共享，所有实例都会共用同一个值，每次实例化新对象时都会覆盖这个全局值。
• 第二：C#的实例字段初始化器（也就是你声明_OriginStartingLevels时直接赋值的那行代码）执行时机早于构造函数。也就是说你在构造函数里给_CharacterOrigin赋值之前，_OriginStartingLevels就已经完成了初始化，用的是赋值前的旧_CharacterOrigin值。

两次实例化的实际执行顺序如下：

1. 第一次实例化Milquetoast类型的OriginModel：
   1. 先执行_OriginStartingLevels初始化，此时静态_CharacterOrigin还未赋值，默认是枚举的0值也就是Milquetoast，所以属性初始化正确为11
   2. 执行构造函数，把静态_CharacterOrigin设为Milquetoast
2. 第二次实例化Lone Survivor类型的OriginModel：
   1. 先执行_OriginStartingLevels初始化，此时静态_CharacterOrigin还是上一步的Milquetoast，所以初始化出来的属性还是11
   2. 执行构造函数，才把静态_CharacterOrigin改成Lone Survivor，但此时属性已经初始化完成，不会再更新

这就是Lone Survivor实例的vitality值不符合预期的原因，添加更多实例时，每个实例的属性都会用前一个实例设置的静态_CharacterOrigin值初始化，所以会出现前几个属性重复的情况。

修复方案 #

1. 删掉无用的静态字段public static OriginType _CharacterOrigin;，不需要这个全局共享字段
2. 把_OriginStartingLevels的初始化放到构造函数里执行，用当前实例的出身类型传参，修改后的代码参考：

using BloodBorneTableTopGame.Models.PlayerStatsModel;

namespace BloodBorneTableTopGame.Models.OriginModels
{
    public class OriginModel
    {
        // 删掉了静态_CharacterOrigin字段
        public OriginModel(OriginType origin)
        {
            CharacterOrigin = origin;
            // 构造函数内再初始化属性，用当前实例的出身类型
            _OriginStartingLevels = new PlayerStatModel(origin);
        }
        public enum OriginType
        {
            Milquetoast,
            LoneSurvivor,
            TroubledChildhood,
            ViolentPast,
            Professional,
            MilitaryVeteran,
            NobleScion,
            CruelFate,
            WasteOfSkin
        }

        public OriginType CharacterOrigin;

        public string OriginName { get { return GetName(CharacterOrigin); } }

        public string OriginDescription { get { return Description(CharacterOrigin); } }
        public string Description(OriginType origin) =>
            origin switch
            {
                OriginType.Milquetoast => "Ordinary, happy upbringing. All attributes average.",
                OriginType.LoneSurvivor => "Lone survivor of lost hamlet. High life essence and vigor.",
                OriginType.TroubledChildhood => "Suffered misfortune in youth. Highly resilient as a result.",
                OriginType.ViolentPast => "Terribly violent past. Rash, but stronger for it.",
                OriginType.Professional => "Born specialist, fit for sleuthing or academia.",
                OriginType.MilitaryVeteran => "Experienced in war. A soldier with strength and skill.",
                OriginType.NobleScion => "Scion to a respectable line with faith in your pedigree.",
                OriginType.CruelFate => "Faced terrible hardships, but now confident in your purpose.",
                OriginType.WasteOfSkin => "You are nothing. Talentless. You shouldn't have been born.",
                _ => "Error: No Origin Type Selected"
            };
        public string GetName(OriginType origin) =>
            origin switch
            {
                OriginType.Milquetoast => "Milquetoast",
                OriginType.LoneSurvivor => "Lone Survivor",
                OriginType.TroubledChildhood => "Troubled Childhood",
                OriginType.ViolentPast => "Violent Past",
                OriginType.Professional => "Professional",
                OriginType.MilitaryVeteran => "Military Veteran",
                OriginType.NobleScion => "Noble Scion",
                OriginType.CruelFate => "Cruel Fate",
                OriginType.WasteOfSkin => "Waste of Skin",
                _ => "Error: No Origin Type Selected"
            };

        // 声明时不再初始化
        private PlayerStatModel _OriginStartingLevels;

        public PlayerStatModel OriginStartingLevels { get => _OriginStartingLevels;  }
    }
}

内容的提问来源于stack exchange，提问作者dsmith1515