【DEMO】【C/C++】最简单的一种回调函数

回调函数最简单用法

// CallBackFunc.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 <string>
using namespace std;
 
 
string toZeroDown(int n, void *contex) {
	cout  << "toZeroDown:" << -*(int*)(contex) << endl;
	return "toZeroDown";
}
 
string toZeroUp(int n, void *contex) {
	cout << "toZeroUp:" << *(int*)(contex) << endl;
	return "toZeroUp";
}
 
typedef string(*CallBackFunc)(int n, void *contex);
 
void registNumCallBack(CallBackFunc callback, void *contex)
{
	int n = 3;
	cout << "The Option of 'callback()' is:" << callback(n, contex) << endl;
}
 
int main()
{
	for (int i = 0; i < 10; i++)
	{
		if (i % 2) {
			registNumCallBack(toZeroDown, &i);
		}
		else
		{
			registNumCallBack(toZeroUp, &i);
		}
	}
	
}

输出：

toZeroUp:0
The Option of 'callback()' is:toZeroUp
toZeroDown:-1
The Option of 'callback()' is:toZeroDown
toZeroUp:2
The Option of 'callback()' is:toZeroUp
toZeroDown:-3
The Option of 'callback()' is:toZeroDown
toZeroUp:4
The Option of 'callback()' is:toZeroUp
toZeroDown:-5
The Option of 'callback()' is:toZeroDown
toZeroUp:6
The Option of 'callback()' is:toZeroUp
toZeroDown:-7
The Option of 'callback()' is:toZeroDown
toZeroUp:8
The Option of 'callback()' is:toZeroUp
toZeroDown:-9
The Option of 'callback()' is:toZeroDown

原文：https://blog.csdn.net/Fuel_Ming/article/details/122950838