C语言进阶课程学习记录-第36课

C语言进阶课程学习记录-第36课 - 函数与指针分析

- 函数类型
- 实验-函数指针
- 实验-回调机制
- 小结

本文学习自狄泰软件学院唐佐林老师的 C语言进阶课程，图片全部来源于课程PPT，仅用于个人学习记录

函数类型

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实验-函数指针

#include <stdio.h>

typedef int(FUNC)(int);

int test(int i)
{
    return i * i;
}

void f()
{
    printf("Call f()...\n");
}

int main()
{
    FUNC* pt = test;
    //void(*pf)() = &f;
    void(*pf)() = (int *)0x00401340;//ok
    printf("pf = %p\n", pf);
    printf("f = %p\n", f);
    printf("&f = %p\n", &f);

    pf();

    (*pf)();

    printf("Function pointer call: %d\n", pt(2));

    return 0;
}

    /*
    output:
pf = 00401340
f = 00401340
&f = 00401340
Call f()...
Call f()...
Function pointer call: 4

    */

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实验-回调机制

#include <stdio.h>

typedef int(*Weapon)(int);

void fight(Weapon wp, int arg)
{
    int result = 0;

    printf("Fight boss!\n");

    result = wp(arg);

    printf("Boss loss: %d\n", result);
}

int knife(int n)
{
    int ret = 0;
    int i = 0;

    for(i=0; i<n; i++)
    {
        printf("Knife attack: %d\n", 1);
        ret++;
    }

    return ret;
}

int sword(int n)
{
    int ret = 0;
    int i = 0;

    for(i=0; i<n; i++)
    {
        printf("Sword attack: %d\n", 5);
        ret += 5;
    }

    return ret;
}

int gun(int n)
{
    int ret = 0;
    int i = 0;

    for(i=0; i<n; i++)
    {
        printf("Gun attack: %d\n", 10);
        ret += 10;
    }

    return ret;
}

int main()
{
    fight(knife, 3);
    fight(sword, 4);
    fight(gun, 5);

    return 0;
}

    /*
    output:
Fight boss!
Knife attack: 1
Knife attack: 1
Knife attack: 1
Boss loss: 3
Fight boss!
Sword attack: 5
Sword attack: 5
Sword attack: 5
Sword attack: 5
Boss loss: 20
Fight boss!
Gun attack: 10
Gun attack: 10
Gun attack: 10
Gun attack: 10
Gun attack: 10
Boss loss: 50

    */