shared_ptr智能指针

// Test.cpp : 定义控制台应用程序的入口点。
//

#include "stdafx.h"
#include <thread>
#include <memory>
#include <iostream>
#include <assert.h>
#include <thread>
#include<windows.h>


#define OPEN_IF 1
#define CLOSE_IF 0

class B
{
public:
    B()
    {
        std::cout << "B Create" << std::endl;
    }
    ~B()
    {
        std::cout << "B Destroy" << std::endl;
    }
    void fun()
    {
        std::cout << "B fun" << std::endl;
    }
private:
};

void threadFun(std::shared_ptr<B> ptr)
{
    int count = 5;
    auto source = ptr.get();
    std::cout << "thread ptr:" << ptr << std::endl;
#if CLOSE_IF
    std::cout << "source address:" << source << std::endl;
    std::cout << "current thread id:" << GetCurrentThreadId() << std::endl;
#endif 
    while (count--)
    {
        ptr->fun();
        Sleep(1000);
    }
    ptr.reset();
    std::cout << "B after use count:" << ptr.use_count() << std::endl;    
}

int main()
{
    B *b = new B();
    std::shared_ptr<B> myPtr1(b);
    std::cout << "source ptr:" << myPtr1 << std::endl;
    std::thread threadA(threadFun, myPtr1);
    std::cout << "B before use count:" << myPtr1.use_count() << std::endl;
    threadA.detach();
    myPtr1.reset();

    getchar();
    return 0;
}

注意：shared_ptr作为参数【函数参数、线程参数】时，不管是不是引用传递，都是拷贝复制，所以它们的计数器是同一个，所以计数+1