Programming-Design-Patterns-And-Principles/Assets/_test/Singleton/MonoSingleton/MonoSingleton.cs

using System;
using UnityEngine;

namespace _test.Singleton.MonoSingleton
{
    public abstract class MonoSingleton<T> : MonoBehaviour where T : MonoSingleton<T>
    {
        public static T Instance { get; private set; }

        protected virtual void Awake()
        {
            if (Instance != null && Instance != this)
            {
                Destroy(gameObject);
                return;
            }

            Instance = (T)this;
            DontDestroyOnLoad(gameObject);
        }
    }
}