CSharp中实现一个可继承的Singleton基类

网上大部分的单例实现都要求在类里添加一个”GetInstance()”并且声明私有的构造函数,额外多了几行没啥用且重复的代码,一不小心还会忘记把构造函数搞成私有的,非常不爽,所以就搞了个这东西

不多说,上代码,使用的时候只需要public class ClassName : Singleton<ClassName>即可,获取实例直接ClassName.Instance,无需额外的更改

using System;
using System.Collections.Generic;

namespace InstanceHelper.Singleton {
    public class Singleton<T> {
        private static Dictionary<Type, Object> TypeObjectMap = new Dictionary<Type, Object>();
        private static List<Type> TypeLoadList = new List<Type>();

        static public T Instance { get => GetInstance(typeof(T)); }

        public Singleton() {
            lock (TypeLoadList) {
                if (!TypeLoadList.Contains(this.GetType())) {
                    throw new NewSingletonClassException(String.Format("Class {0} is Singleton, Use \"{1}.Instance;\" but \"new {1}();\"", this.GetType().FullName, this.GetType().Name));
                }
            }
        }

        private static void LockUnregisterTypeLoadStatus(Type _Type) {
            lock (TypeLoadList) {
                if (TypeLoadList.Contains(_Type)) {
                    TypeLoadList.Remove(_Type);
                }
            }
        }

        private static void LockRegisterTypeLoadStatus(Type _Type) {
            lock (TypeLoadList) {
                if (!TypeLoadList.Contains(_Type)) {
                    TypeLoadList.Add(_Type);
                }
            }
        }

        protected static T GetInstance(Type _Type) {
            if (!TypeObjectMap.ContainsKey(_Type)) {
                lock (TypeObjectMap) {
                    if (!TypeObjectMap.ContainsKey(_Type)) {
                        LockRegisterTypeLoadStatus(_Type);
                        var Instance = Activator.CreateInstance(_Type);
                        LockUnregisterTypeLoadStatus(_Type);
                        TypeObjectMap.Add(_Type, Instance);
                    }
                }
            }
            return (T)TypeObjectMap[_Type];
        }
    }
}