1. 简单测试代码

// funcTest.cpp : 此文件包含 "main" 函数。程序执行将在此处开始并结束。
//

#include <iostream>
#include <functional>
#include <iostream>

using namespace std;
class Tx
{
public:
    void printNum(int i)
    {
        cout << "i am " << i << endl;
    }
};

void testFunc(std::function<void(int)>& funcObj)
{

    int kk = 1024;
    for (int i = 0; i < kk; i++)
    {
        cout << i << endl;
    }

    funcObj(kk);

}

int main()
{
    std::cout << "Hello World!\n";

    Tx obj;
    std::function<void(int)> f_display_obj = std::bind(&Tx::printNum, &obj, std::placeholders::_1);
    testFunc(f_display_obj);
}