数据结构图书管理系统c语言代码如何实现

下面是一个简单的数据结构图书管理系统的C语言代码实现，包括书籍的增加、删除、查询和修改等功能。具体实现方法如下：

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

// 定义图书结构体
typedef struct book {
    int id;                 // 编号
    char name[20];          // 书名
    char author[20];        // 作者
    char press[20];         // 出版社
    float price;            // 价格
    struct book *next;
} Book;

// 定义全局变量
Book *head = NULL;          // 头结点指针

// 函数声明
void add_book();
void delete_book();
void search_book();
void modify_book();
void display_book();
void save_book();
void load_book();

// 主函数
int main() {
    int choice;

    // 加载图书数据
    load_book();

    while (1) {
        printf("\n");
        printf("1. Add book\n");
        printf("2. Delete book\n");
        printf("3. Search book\n");
        printf("4. Modify book\n");
        printf("5. Display books\n");
        printf("6. Save books\n");
        printf("7. Exit\n");
        printf("Enter your choice: ");
        scanf("%d", &choice);

        switch (choice) {
            case 1:
                add_book();
                break;
            case 2:
                delete_book();
                break;
            case 3:
                search_book();
                break;
            case 4:
                modify_book();
                break;
            case 5:
                display_book();
                break;
            case 6:
                save_book();
                break;
            case 7:
                // 退出程序前保存数据
                save_book();
                exit(0);
            default:
                printf("Invalid choice!\n");
        }
    }

    return 0;
}

// 添加图书
void add_book() {
    Book *p, *tail;

    // 创建新结点
    p = (Book *) malloc(sizeof(Book));
    if (p == NULL) {
        printf("Memory allocation failed!\n");
        return;
    }

    // 输入图书信息
    printf("Enter book id: ");
    scanf("%d", &p->id);
    printf("Enter book name: ");
    scanf("%s", p->name);
    printf("Enter book author: ");
    scanf("%s", p->author);
    printf("Enter book press: ");
    scanf("%s", p->press);
    printf("Enter book price: ");
    scanf("%f", &p->price);

    // 将新结点插入链表尾部
    p->next = NULL;
    if (head == NULL) {
        head = p;
    } else {
        tail = head;
        while (tail->next != NULL) {
            tail = tail->next;
        }
        tail->next = p;
    }

    printf("Book added successfully!\n");
}

// 删除图书
void delete_book() {
    int id;
    Book *p, *prev;

    // 输入图书编号
    printf("Enter book id: ");
    scanf("%d", &id);

    // 查找对应结点
    p = head;
    prev = NULL;
    while (p != NULL) {
        if (p->id == id) {
            break;
        }
        prev = p;
        p = p->next;
    }

    if (p == NULL) {
        printf("Book not found!\n");
        return;
    }

    // 删除结点
    if (prev == NULL) {
        head = p->next;
    } else {
        prev->next = p->next;
    }
    free(p);

    printf("Book deleted successfully!\n");
}

// 查找图书
void search_book() {
    int id;
    Book *p;

    // 输入图书编号
    printf("Enter book id: ");
    scanf("%d", &id);

    // 查找对应结点
    p = head;
    while (p != NULL) {
        if (p->id == id) {
            printf("Book id: %d\n", p->id);
            printf("Book name: %s\n", p->name);
            printf("Book author: %s\n", p->author);
            printf("Book press: %s\n", p->press);
            printf("Book price: %.2f\n", p->price);
            break;
        }
        p = p->next;
    }

    if (p == NULL) {
        printf("Book not found!\n");
    }
}

// 修改图书
void modify_book() {
    int id;
    Book *p;

    // 输入图书编号
    printf("Enter book id: ");
    scanf("%d", &id);

    // 查找对应结点
    p = head;
    while (p != NULL) {
        if (p->id == id) {
            break;
        }
        p = p->next;
    }

    if (p == NULL) {
        printf("Book not found!\n");
        return;
    }

    // 修改结点信息
    printf("Enter new book name: ");
    scanf("%s", p->name);
    printf("Enter new book author: ");
    scanf("%s", p->author);
    printf("Enter new book press: ");
    scanf("%s", p->press);
    printf("Enter new book price: ");
    scanf("%f", &p->price);

    printf("Book modified successfully!\n");
}

// 显示图书
void display_book() {
    Book *p;

    printf("--------------------\n");
    printf("ID | Name | Author | Press | Price\n");
    printf("--------------------\n");

    // 遍历链表输出信息
    p = head;
    while (p != NULL) {
        printf("%d | %s | %s | %s | %.2f\n", p->id, p->name, p->author, p->press, p->price);
        p = p->next;
    }
}

// 保存图书
void save_book() {
    FILE *fp;
    Book *p;

    // 打开文件
    fp = fopen("book.txt", "w");
    if (fp == NULL) {
        printf("File open failed!\n");
        return;
    }

    // 遍历链表写入文件
    p = head;
    while (p != NULL) {
        fprintf(fp, "%d %s %s %s %.2f\n", p->id, p->name, p->author, p->press, p->price);
        p = p->next;
    }

    // 关闭文件
    fclose(fp);

    printf("Books saved successfully!\n");
}

// 加载图书
void load_book() {
    FILE *fp;
    Book *p, *tail;
    int id;
    char name[20], author[20], press[20];
    float price;

    // 打开文件
    fp = fopen("book.txt", "r");
    if (fp == NULL) {
        printf("File open failed!\n");
        return;
    }

    // 读取文件内容并插入链表
    while (fscanf(fp, "%d %s %s %s %f", &id, name, author, press, &price) != EOF) {
        p = (Book *) malloc(sizeof(Book));
        if (p == NULL) {
            printf("Memory allocation failed!\n");
            return;
        }
        p->id = id;
        strcpy(p->name, name);
        strcpy(p->author, author);
        strcpy(p->press, press);
        p->price = price;
        p->next = NULL;

        if (head == NULL) {
            head = p;
        } else {
            tail = head;
            while (tail->next != NULL) {
                tail = tail->next;
            }
            tail->next = p;
        }
    }

    // 关闭文件
    fclose(fp);

    printf("Books loaded successfully!\n");
}

此代码实现了一个简单的图书管理系统，可以通过菜单选择进行图书的增加、删除、查询、修改、显示、保存和加载等操作。其中，图书的信息以链表形式存储，保存在文件book.txt中，程序启动时会将文件中的数据加载到链表中，程序结束时会将链表中的数据保存到文件中，以便下次启动时使用。