Question

我是一名相对较新的程序员，目前正在大学学习C language。对于我的项目，我的任务是为学生设计一个图书馆系统，每当我尝试删除最近编辑过的同一本书时，我一直遇到debug assertion failed - 错误。有人可以帮我解决这个问题吗？

PS：我必须在几天内提交该程序＆＃39;时间，所以我需要一些帮助！ d：

这是我编辑书籍的代码：

void EditBookInformation()
{
    int found = 0;
    char user_input[5];
    system("cls");
    printf("You have selected Edit Book Information \n");
    printf("Please enter the Book ID to edit the book: \n");
    scanf_s(" %s", &user_input, 5);
    fflush(stdin);
    fopen_s(&BookList, "record.txt", "rb+");
    fopen_s(&BookList2, "newrecord.txt", "wb+");
    fopen_s(&Logsheet, "log.txt", "a+");
    rewind(BookList);
    rewind(BookList2);
    while (fread(&Books, sizeof(Books), 1, BookList) != NULL)
    {
        if (strcmp(user_input, Books.Book_ID) == 0)
        {
            found = 1;
            printf("Book has been found! \n");
            printf("\nBook ID:%s \n", Books.Book_ID);
            printf("Title:%s \n", Books.Title);
            printf("Edition:%s \n", Books.Edition);
            printf("Year of publication:%s \n", Books.Year_of_publication);
            printf("Shelf location:%s \n", Books.Shelf_location);
            printf("Price in RM:%s \n", Books.Price);
            break;
        }
        else
        {
            fwrite(&Books, sizeof(Books), 1, BookList2);
        }
    }

    if (!found)
    {
        printf("Book not found! \n");
        _fcloseall();
        system("pause");
        system("cls");
        main();
    }

    char confirm;
    printf("\nDo you want to edit this book?");
    scanf_s("%c", &confirm);
    fflush(stdin);


    if (confirm == 'y')
    {
        printf("New Title:");
        scanf_s("%[^\n]s", &Books.Title, 50);
        while (getchar() != '\n');

        printf("New Edition:");
        scanf_s("%s", &Books.Edition, 6);
        while (getchar() != '\n');

        NewYearInput:
        printf("New Year of publication:");
        scanf_s("%s", &Books.Year_of_publication, 5);
        while (getchar() != '\n');
        int length = strlen(Books.Year_of_publication);
        int digit = 0;
        if (length == 4)
        {
            for (; digit < length; digit++)
            if (!isdigit(Books.Year_of_publication[digit]))
                break;
        }
        if (digit != 4)
        {
            printf("Wrong input! Please enter 4 digits for year! \n");
            system("pause>nul");
            goto NewYearInput;
        }

        printf("New Shelf Location:");
        scanf_s("%s", &Books.Shelf_location, 5);
        while (getchar() != '\n');

        printf("New Price in RM:");
        scanf_s("%s", &Books.Price, 5);
        while (getchar() != '\n');

        fprintf(Logsheet, "Book edited: %s \n", Books.Title);
        fseek(BookList, ftell(BookList) -sizeof(Books), SEEK_SET);
        fwrite(&Books, 1, sizeof(Books), BookList);
        fclose(BookList);
        fclose(Logsheet);
        printf("Book has been edited! \n");
        printf("Press any key to return to main menu \n");
        system("pause>nul");
        system("cls");
        main();
    }
    else if (confirm == 'n')
    {   
        printf("You have cancelled your operation! \n");
        _fcloseall();
        system("cls");
        main();
    }
}

以下是我删除图书的代码：

void DeleteBookByBookID()
{
    int found = 0;
    char user_input1[5];
    system("cls");
    printf("You have selected Delete Book \n");
    printf("Please enter the Book ID that you want to delete the book \n");
    scanf_s("%s", &user_input1, 5);
    fflush(stdin);
    fopen_s(&BookList, "record.txt", "rb+");
    fopen_s(&BookList2, "newrecord.txt", "wb+");
    fopen_s(&Logsheet, "log.txt", "a+");

    rewind(BookList);
    rewind(BookList2);

    while (fread(&Books, sizeof(Books), 1, BookList) != NULL)
    {
        if (strcmp(user_input1, Books.Book_ID) == 0)
        {
            printf("Book found! \n");
            found = 1; 
        }
        else
        {
            fwrite(&Books, sizeof(Books), 1, BookList2);
        }
    }
    if (!found)
    {
        printf("Book ID not found! \n");
        _fcloseall();
        system("pause");
        system("cls");
        main();
    }
    fclose(BookList);
    fclose(BookList2);

    char confirm;
    printf("Do you want to delete this book? \n");
    scanf_s(" %c", &confirm);
    fflush(stdin);

    if (confirm == 'y')
    {
        remove("record.txt");
        rename("newrecord.txt", "record.txt");
        fprintf(Logsheet, "Book deleted: %s \n", Books.Title);
        printf("Book has been deleted! \n");
        printf("Press any key to return to main menu \n");
        system("pause>nul");
        system("cls");
        main();
    }
    else if (confirm == 'n')
    {
        printf("You have cancelled your operation! \n");
        fclose(BookList);
        fclose(BookList2);
        system("cls");
        main();
    }
    fclose(Logsheet);
}

Answer 1

如果找不到图书，则表示您正在致电main。但是用户不应该调用main。它由系统调用，是程序的开始。也许你的意思是return？

您正在阅读BookList，如果读取的记录不是您想要的记录，则将其写入BookList2。找到记录后，编辑它然后将其写入BookList2，然后关闭文件并将新文件重命名为旧文件。但旧文件中的所有剩余记录会发生什么？你不应该将它们复制到新文件中吗？

另请参阅有关其他有用消息的帖子的评论。

调试断言无法编辑和删除记录

1 个答案: