C：取消引用指向不完整类型错误的指针

Question

我在 C 中创建了一个联系人链接列表。它运行良好。但现在我想为指定的联系人（按姓名）编写删除函数，我得到了Error:"dereferencing pointer to incomplete type"。这是我的代码：

struct contact
{
    char name[100];
    char number[20];
    struct contact *next;
};
int deleteByName(struct contact **hptr, char *name)
{
    struct student *prev = NULL;
    struct student *temp = *hptr;
    while (strcmp(temp->name /*The Error is Here*/ , name) != 0 && (temp->next) != NULL)
    {
        prev = temp;
        temp = temp->next; 
    }
    if (strcmp(temp->name, name) == 0)
    {
        if (prev == NULL)
            *hptr = temp->next;
        else
            prev->next = temp->next;
        free(temp);
        return 0;
    }
    printf("\nNAME '%s' WAS NOT FOUND TO BE DELETED.", name);
    return -1;
}

我想知道为什么我会收到这个错误（尽管定义了 struct contact.）。谢谢。

Answer 1

您的 next 指针类型是 contact - 假设这是一个错字 - 这是修正了错字的更正代码 - 这可以编译 - HTH！

struct student
{
    char name[100];
    char number[20];
    struct student *next;
};

int deleteByName(struct student **hptr, char *name)
{
    struct student *prev = NULL;
    struct student *temp = *hptr;
    while (strcmp(temp->name, name) != 0 && (temp->next) != NULL)
    {
        prev = temp;
        temp = temp->next; //***No Error now***
    }
    if (strcmp(temp->name, name) == 0)
    {
        if (prev == NULL)
            *hptr = temp->next;
        else
            prev->next = temp->next;
        free(temp);
        return 0;
    }
    printf("\nNAME '%s' WAS NOT FOUND TO BE DELETED.", name);
    return -1;
}