1. Description
通过链来实现简单的图书管理系统，实现如下功能：
1. 添加图书
2. 查询图书信息
3. 修改图书价格
4. 删除图书
5. 查看所有图书
6. 退出
需要熟悉结构体和指针的使用，具有简单的数据结构链表概念。还需要处理好一些细节，充分考虑到各种情况，比如没有图书或查询不到图书，在退出时候所有申请的内存空间是否已经释放掉了等等。写的过程中也是碰到各种bug然后通过调试不断来解决。
2. Code
编译环境：Visual Studio 2017
main.h
#pragma once
#include<stdio.h>
#include<stdlib.h>
#include<string.h>
typedef struct bookNode {
char bookName[50];
int bookNum;
float bookPrice;
struct bookNode *nextBookNode;
}bookNode;
bookNode *appendBook(bookNode *head);
void *searchBook(bookNode *head);
void modifyBook(bookNode *head);
bookNode *deleteBook(bookNode *head);
void freeAllNode(bookNode *head);
void showAllBook(bookNode *head);
main.c
#include "main.h"
int main(void) {
int option;
bookNode *head = NULL;
printf("1. 添加图书\n");
printf("2. 查询图书信息\n");
printf("3. 修改图书价格\n");
printf("4. 删除图书\n");
printf("5. 查看所有图书\n");
printf("6. 退出\n");
while(printf("\n>请输入选项：") && (scanf("%d", &option) == 1))
{
switch (option)
{
case 1:
head = appendBook(head);
break;
case 2:
searchBook(head);
break;
case 3:
modifyBook(head);
break;
case 4:
head = deleteBook(head);
break;
case 5:
showAllBook(head);
break;
case 6:
freeAllNode(head);
break;
default:
printf("错误选项，请重新输入。\n");
break;
}
}
}
bookNode *appendBook(bookNode * head)
{
bookNode *book = (bookNode*)malloc(sizeof(bookNode));
printf("请输入添加图书的书名：");
scanf("%s", book->bookName);
printf("请输入添加图书的编号：");
scanf("%d", &book->bookNum);
printf("请输入添加图书的价格：");
scanf("%f", &book->bookPrice);
book->nextBookNode = NULL;
if (head == NULL) {
head = book;
}
else {
bookNode *pNode = head;
while (pNode->nextBookNode != NULL) {
pNode = pNode->nextBookNode;
}
pNode->nextBookNode = book;
}
printf("图书添加成功！\n");
return head;
}
void *searchBook(bookNode * head)
{
bookNode *pNode = head;
if (pNode == NULL) {
printf("暂无图书\n");
return NULL;
}
else {
printf("请输入查找图书的书名: ");
char bookName[50] = {
0};
scanf("%s", bookName);
printf("查询结果：\n");
if (strcmp(bookName, pNode->bookName) == 0) {
printf("图书书名：%s\n", pNode->bookName);
printf("图书编号：%d\n", pNode->bookNum);
printf("图书价格：%.2f\n", pNode->bookPrice);
return pNode;
}
while (pNode->nextBookNode != NULL) {
pNode = pNode->nextBookNode;
if (strcmp(bookName, pNode->bookName) == 0) {
printf("图书书名：%s\n", pNode->bookName);
printf("图书编号：%d\n", pNode->bookNum);
printf("图书价格：%.2f\n", pNode->bookPrice);
return pNode;
}
}
printf("暂无此书\n");
return NULL;
}
}
void modifyBook(bookNode * head)
{
char bookName[50];
float newBookPrice;
bookNode *pNode = head;
if (pNode == NULL) {
printf("暂无图书\n");
}
else {
printf("请输入要修改价格图书的书名: ");
scanf("%s", bookName);
if (strcmp(bookName, pNode->bookName) == 0) {
printf("请输入修图书改后的价格: ");
scanf("%f", &newBookPrice);
pNode->bookPrice = newBookPrice;
printf("图书价格修改成功!\n");
return;
}
else {
while (pNode->nextBookNode != NULL) {
pNode = pNode->nextBookNode;
if (strcmp(bookName, pNode->bookName) == 0) {
printf("请输入修图书改后的价格: ");
scanf("%f", &newBookPrice);
pNode->bookPrice = newBookPrice;
printf("图书价格修改成功!\n");
return;
}
}
}
printf("暂无此书\n");
}
}
bookNode * deleteBook(bookNode * head)
{
bookNode *pNode = head;
if (pNode == NULL) {
printf("暂无图书\n");
}
char bookName[50];
printf("请输入要删除图书的书名：");
scanf("%s", bookName);
//删除图书为头节点
if (strcmp(bookName, pNode->bookName) == 0) {
head = head->nextBookNode;
free(pNode);
printf("删除成功!\n");
return head;
}
else {
while (pNode->nextBookNode != NULL) {
if (strcmp(bookName, pNode->nextBookNode->bookName) == 0) {
bookNode* tempNode = pNode->nextBookNode;
pNode->nextBookNode = pNode->nextBookNode->nextBookNode;
free(tempNode);
printf("删除成功!\n");
return head;
}
pNode = pNode->nextBookNode;
}
printf("暂无此书\n");
return head;
}
}
void freeAllNode(bookNode * head)
{
bookNode *pNode = head;
while (head != NULL) {
head = head->nextBookNode;
free(pNode);
pNode = head;
}
exit(0);
}
void showAllBook(bookNode * head)
{
if (head == NULL) {
printf("暂无图书\n");
return;
}
else {
printf("所有图书：\n");
bookNode *pNode = head;
printf("%s\n", pNode->bookName);
while (pNode->nextBookNode != NULL) {
pNode = pNode->nextBookNode;
printf("%s\n", pNode->bookName);
}
}
return;
}
3. Show
