C#单例模式的泛型定义

取自某热门网游

using System;

public class Singleton<T> where T : class, new()
{
private static T _Instance;

public static T Instance
{
get
{
if (Singleton<T>._Instance == null)
{
Singleton<T>._Instance = Activator.CreateInstance<T>();
}
return Singleton<T>._Instance;
}
}

static Singleton()
{
Singleton<T>._Instance = Activator.CreateInstance<T>();
}

public static void CreateInstance()
{
if (Singleton<T>._Instance == null)
{
Singleton<T>._Instance = Activator.CreateInstance<T>();
}
}

public static void DestroyInstance()
{
if (Singleton<T>._Instance != null)
{
Singleton<T>._Instance = (T)((object)null);
}
}

public static T GetInstance()
{
if (Singleton<T>._Instance == null)
{
Singleton<T>._Instance = Activator.CreateInstance<T>();
}
return Singleton<T>._Instance;
}
}

using System;
using UnityEngine;

namespace Engine
{
public abstract class MonoSingleton<T> : MonoBehaviour where T : MonoSingleton<T>
{
private static T m_Instance;

public static T Instance
{
get
{
if (MonoSingleton<T>.m_Instance == null)
{
MonoSingleton<T>.m_Instance = (UnityEngine.Object.FindObjectOfType(typeof(T)) as T);
}
return MonoSingleton<T>.m_Instance;
}
}

protected void Awake()
{
if (MonoSingleton<T>.m_Instance == null)
{
MonoSingleton<T>.m_Instance = (this as T);
}
}

private void OnDestroy()
{
MonoSingleton<T>.m_Instance = (T)((object)null);
}

protected void OnApplicationQuit()
{
MonoSingleton<T>.m_Instance = (T)((object)null);
}
}
}