C++ 如何在另一个类中创建结构指针？

我有3个类：Book、Student、LibrarySystem，我需要3个linkedList来存储数据，第一个linkedList称为节点，用于存储学生，第二个linkedList称为studenBookNode，用于存储特定学生保留的图书，第三个linkedList是allBooksNode，用于存储创建的图书对象 以下是我的实现：

class Book {
public:
    Book();
    Book(int id, string title, int year);
    ~Book();
    //some getter and setter functions
private:
    int bookId;
    string bookName;
    int bookYear;
    bool status;
};

class Student {
public:
    Student();
    Student(int id, string name);
    ~Student();
    Student(const Student& rightVal);
    //Student& operator=(const Student& rightVal);
    int getId();
    void setId(int id);
    string getName();
    void setName(string name);
    //studentBookNode methods
    bool isEmpty() const;
    int getLength() const;
    bool removeNode(int index);
    int findIndex(int studentId);
    struct studentBookNode {
        Book item;
        studentBookNode* next;
    };
    studentBookNode* stuhead;
    int studentBooks;
    studentBookNode* findPointer(int index) const;

private:
    int studentId;
    string studentName;
};

class LibrarySystem {
public:
    LibrarySystem();
    ~LibrarySystem();
    void addStudent(const int studentId, const string studentName);
    void addBook(const int bookId, const string bookName, const int bookYear);

    void deleteBook(const int bookId);
    void deleteStudent(const int studentId);
    void checkoutBook(const int bookId, const int studentId);
    void returnBook(const int bookId);
    void showAllBooks() const;
    void showBook(const int bookId) const;
    void showStudent(const int studentId) const;

    bool isEmpty() const;
    bool isBooksEmpty() const;
    bool removeNode(int index);
    bool removeBookNode(int index);

    int findBookIndex(int bookId);
    int findIndex(int studentId);
    int getLengthBooks() const;
    int getLength() const;

private:
    struct Node {
        Student item;
        Node* next;
    };
    Node* head;
    int Size;
    Node* findPointer(int index) const;
    struct allBooksNode {
        Book item;
        allBooksNode* next;
    };
    allBooksNode* bookHead;
    int bookSize;
    allBooksNode* findBookPointer(int index) const;
};

void LibrarySystem::checkoutBook(const int bookId, const int studentId)
{
    bool bookExist = false;
    bool studentExist = false;
    Node* cur = head;
    int stuIndex;
    int bookIndex;
    allBooksNode* curBook = bookHead;
    for (int i = 1; i <= getLengthBooks(); i++) {
        if (curBook->item.getBookId() == bookId) {
            bookExist = true;
            bookIndex = i;
        }
        curBook = curBook->next;
    }
    if (bookExist) {
        for (int i = 1; i <= getLength(); i++) {
            if (cur->item.getId() == studentId) {
                studentExist = true;
                stuIndex = i;
            }
            cur = cur->next;
        }
    }
    else {
        cout << "Book :" << bookId << " does not exist for checkout" << endl;
    }
    if (bookExist == true && studentExist == true) {
        Node* stuTemp = findPointer(stuIndex);
        allBooksNode* bookTemp = findBookPointer(bookIndex);

        if (stuTemp->item.getLength() == 0) {
            //problem is here i cant create studentBookNode* here
          studentBookNode* temp = new studentBookNode();
        }
    }
    else {
        cout << "Student: " << studentId << " does not exist for checkout" << endl;
    }
}

我在LibrarySystem中有一个方法checkOutBook，我需要访问该方法中的studentBookNode，首先我要检查studentId和bookId的可用性，然后如果它们可用，我需要将该书添加到特定的studentBookNode，但由于范围问题，我无法访问它，我如何解决这个问题，以下是我的实现：

class Book {
public:
    Book();
    Book(int id, string title, int year);
    ~Book();
    //some getter and setter functions
private:
    int bookId;
    string bookName;
    int bookYear;
    bool status;
};

class Student {
public:
    Student();
    Student(int id, string name);
    ~Student();
    Student(const Student& rightVal);
    //Student& operator=(const Student& rightVal);
    int getId();
    void setId(int id);
    string getName();
    void setName(string name);
    //studentBookNode methods
    bool isEmpty() const;
    int getLength() const;
    bool removeNode(int index);
    int findIndex(int studentId);
    struct studentBookNode {
        Book item;
        studentBookNode* next;
    };
    studentBookNode* stuhead;
    int studentBooks;
    studentBookNode* findPointer(int index) const;

private:
    int studentId;
    string studentName;
};

class LibrarySystem {
public:
    LibrarySystem();
    ~LibrarySystem();
    void addStudent(const int studentId, const string studentName);
    void addBook(const int bookId, const string bookName, const int bookYear);

    void deleteBook(const int bookId);
    void deleteStudent(const int studentId);
    void checkoutBook(const int bookId, const int studentId);
    void returnBook(const int bookId);
    void showAllBooks() const;
    void showBook(const int bookId) const;
    void showStudent(const int studentId) const;

    bool isEmpty() const;
    bool isBooksEmpty() const;
    bool removeNode(int index);
    bool removeBookNode(int index);

    int findBookIndex(int bookId);
    int findIndex(int studentId);
    int getLengthBooks() const;
    int getLength() const;

private:
    struct Node {
        Student item;
        Node* next;
    };
    Node* head;
    int Size;
    Node* findPointer(int index) const;
    struct allBooksNode {
        Book item;
        allBooksNode* next;
    };
    allBooksNode* bookHead;
    int bookSize;
    allBooksNode* findBookPointer(int index) const;
};

void LibrarySystem::checkoutBook(const int bookId, const int studentId)
{
    bool bookExist = false;
    bool studentExist = false;
    Node* cur = head;
    int stuIndex;
    int bookIndex;
    allBooksNode* curBook = bookHead;
    for (int i = 1; i <= getLengthBooks(); i++) {
        if (curBook->item.getBookId() == bookId) {
            bookExist = true;
            bookIndex = i;
        }
        curBook = curBook->next;
    }
    if (bookExist) {
        for (int i = 1; i <= getLength(); i++) {
            if (cur->item.getId() == studentId) {
                studentExist = true;
                stuIndex = i;
            }
            cur = cur->next;
        }
    }
    else {
        cout << "Book :" << bookId << " does not exist for checkout" << endl;
    }
    if (bookExist == true && studentExist == true) {
        Node* stuTemp = findPointer(stuIndex);
        allBooksNode* bookTemp = findBookPointer(bookIndex);

        if (stuTemp->item.getLength() == 0) {
            //problem is here i cant create studentBookNode* here
          studentBookNode* temp = new studentBookNode();
        }
    }
    else {
        cout << "Student: " << studentId << " does not exist for checkout" << endl;
    }
}

错误消息是

studentBookNode was not declared in this scope

---

studentBookNode

是类

Student

的成员。除非您是

Student

类的成员，否则此名称只能作为

Student:：studentBookNode

访问。您知道许多书籍在其一生中可以更改其名称或版本年份吗？只是问问而已。@n.“代词是m。我无法理解你的问题。这与你的问题完全相切，但仍然。您有

setBookName（）

和

setBookYear（）

。这些函数用于什么？一位图书馆经理是否会在某一天早上醒来后决定，从现在起，“如何防弹你的小猫，2013”应该被称为“1886年，为了娱乐和利润向人们扔蔬菜”？@n.“代词”m.啊，先生，此代码用于大学作业，禁止更改获取/设置方法，我的问题是如何在LibrarySystem类中访问studenBookNode？@n.“代词m。如何修复打字错误或不正确的数据？