一个单例模式的实现

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欢迎大家点评，这是个人写的一个单例模板

#pragma once

//单例模板
#include <windows.h>

class CrsLock
{
public:
	CrsLock(){ 
		InitializeCriticalSection(&m_crs); 
	}
	~CrsLock(){ 
		DeleteCriticalSection(&m_crs); 
	}
	void Enter() { 
		EnterCriticalSection(&m_crs); 
	}
	void Leave() {
		LeaveCriticalSection(&m_crs); 
	}
private:
	CRITICAL_SECTION m_crs;
};

template<class T>
class MMSingleton{
public:
	static T& Instance(){
		if (!m_pT){
			m_lock.Enter();
			if (!m_pT){
				m_pT = new T;
			}
			m_lock.Leave();
		}
		return *m_pT;
	}
	static void FreeInstance(){
		if (m_pT){
			m_lock.Enter();
			if (m_pT){
				delete m_pT;
				m_pT = NULL;
			}
			m_lock.Leave();
		}
	}
protected:
	static T* m_pT;
	static CrsLock m_lock;
};

template<class T>
T* MMSingleton<T>::m_pT = NULL;

template<class T>
CrsLock MMSingleton<T>::m_lock;