C/C++回掉函数

参考：https://www.cnblogs.com/chenyuming507950417/archive/2012/01/02/2310114.html

#include <stdio.h>typedef void (*P)(void);void fun1(void){    printf("hello world\n");}void fun2(void){    printf("cbs\n");}int main(void){    P p;    p = fun1;    p();    p = fun2;    p();    return 0;}

#include <stdio.h>typedef void (*P)(void);void printf_text(void){    printf("hello world\n");}void call_printf_text(P p){    p();}int main(void){    P p = printf_text;    call_printf_text(p);    return 0;}

#include <stdio.h>typedef void (*P)(const char *);void printf_text(const char *str){    printf("%s\n",str);}void call_printf_text(P p,const char *str){    p(str);}int main(void){    P p = printf_text;    call_printf_text(p,"hello cbs");    return 0;}

#include <stdio.h>#include <string.h>/************上级的代码*************/typedef void (*P1)(const char *);typedef void (*P2)(const char *,int);typedef struct{    P1 p1;    P2 p2;}Fun;void call(Fun *funs){    const char *str1 = "shun";    const char *str2 = "com";    int len = strlen(str2);    funs->p1(str1);//运行时call    funs->p2(str2,len);//运行时call}/***********************************//************程序员根据上级的typedef定义并实现自己的方法****************/void fun1(const char *str){    printf("%s\n",str);}void fun2(const char *str,int len){    printf("%s\n",str);    printf("%d\n",len);}Fun funs = {fun1,fun2};/******************最后根据上级的结构体打包函数指针*********************/int main(void){    call(&funs);        return 0;}