C++单例小例子

 

#pragma once
class CDoctor
{

private:
 CDoctor(void);
public:
 ~CDoctor(void);

static CDoctor* Instance();

public:
 void Display();

private:
 static CDoctor* instance;
};

#include "Doctor.h"
#include <iostream>
using namespace std;
CDoctor::CDoctor(void)
{
}

CDoctor::~CDoctor(void)
{
}

 

CDoctor *CDoctor::instance = NULL;

CDoctor* CDoctor::Instance()
{ 
 if(NULL == instance)
  instance = new CDoctor();
 return instance;
}

void CDoctor::Display()
{
 cout << "Doctor Display" << endl;
}

#include <string>
#include "Doctor.h"
#include <iostream>
using namespace std;
void main()
{
 string welcome = "hello world";
 cout << welcome << endl;

 CDoctor::Instance()->Display();
 int wait;
 cin >> wait ;
}