Java程序员学习C++之函数指针

函数指针的定义：

头文件：function.h

//该头文件定义了接口，在实际的源文件中定义了模板方法//后续的调用类只需要实现覆盖before，process，after方法即可实现模板方法的回调/*extern可置于变量或者函数前，以表示变量或者函数的定义在别的文件中，提示编译器遇到此变量或函数时，在其它模块中寻找其定义。*/extern void(*before)();extern void(*process)(int,int);extern void(*after)();void my_function(int a,int b);

源文件main.cpp

#include "function.h"#include <iostream>using namespace std;extern void dosth();//static标记该方法的作用域为该模块（文件）内static void before_pro(){cout << "main.before_pro" << endl;}static void process_pro(int a, int b){cout << "main.process_pro" << endl;}static void after_pro(){cout << "main.after_pro" << endl;}//void my_function(int a, int b)//{//before();//process(a, b);//after();//}int main(){before = before_pro;process = process_pro;after = after_pro;my_function(2,3);dosth();return 0;}

源文件：test.cpp

#include <iostream>#include "function.h"using namespace std;void(*before)();void(*process)(int, int);void(*after)();static void before_pro(){cout << "test.before_pro" << endl;}static void process_pro(int a, int b){cout << "test.process_pro" << endl;}static void after_pro(){cout << "test.after_pro" << endl;}void dosth(){before = before_pro;process = process_pro;after = after_pro;my_function(2, 3);}void my_function(int a, int b){before();process(a, b);after();}