如何在函数定义中访问Struct数组的字段？

Question

我是一名编程新手，我在学习DMA和尝试同时使用结构和指针时遇到了困难.我正在做一个程序，它接收有关书籍的信息，并将作者和标题存储在一个结构数组中以显示出来，它需要DMA将字符串存储在结构中。

我最难理解和试图解决的是，当我试图在一个函数定义中访问Struct数组的字段，例如。

void getInfo(struct BookInfo *pbook, char author[], char title[])
{
     //creating memory for strings 
     pbook.author = (struct BookInfo*) malloc((strlen(author) +1) * sizeof(char));       
     pbook.title = (struct BookInfo*) malloc((strlen(title) +1) * sizeof(char)); 

     //copying info into the heap
     strcopy(pbook.author, author);
     strcopy(pbook.title, title);

}


I would really appreciate your help in any way, thanks in advance

这是我的完整代码

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

#define size 5   //size is the total number of elements in the array

//declaration of struct
struct BookInfo {

    char* author;
    char* title;
};

//prototypes
void getInfo(struct BookInfo *pbook, char author[], char title[]);
void printInfi(struct BookInfo book[]);

int main() {

    struct BookInfo myBook[size];    //declare an array.
    char author[40] = { '0' };   //temp strings to store input from user
    char title[50] = { '0' };


    //get input from user
    printf("Enter author name: ");
        fgets(author, 40, stdin);

    printf("Enter book title name: ");
        fgets(title, 50, stdin);


   // call function to store info (dma) individually in array, loop 5 times do fill struct array 
     for(int i =0; i < size; i++)
         {
             void getInfo(struct BookInfo myBook, author, title);
         }

   // call function to print all info from array, call one time
      void printInfi(struct BookInfo myBook);

   // Free space from dma
       for(int i=0; i < size; i++)
           {
              free(myBook[i].author);
              free(myBook[i].title); 
           }

    return 0;
}


void getInfo(struct BookInfo *pbook, char author[], char title[])
{
     //creating memory for strings 
     pbook.author = (struct BookInfo*) malloc((strlen(author) +1) * sizeof(char));       
     pbook.title = (struct BookInfo*) malloc((strlen(title) +1) * sizeof(char)); 

     //copying info into the heap
     strcopy(pbook.author, author);
     strcopy(pbook.title, title);

}

void printInfo(struct BookInfo book[])
{
     for(int i = 0; i < size; i++)   
         {
             printf("Title: %s, Author: %s\n", book[i].author, book[i].title);
         }

}

Answer 1

如果你有一个结构指针的例子。struct structName *pToAStruct;，访问... 价值 外地使用 -> 像这样的操作者: var = pToAStruct->field. 用 var 和 field 具有相同的类型， int 比如说，如果你有一个直接的结构变量，那么就使用结构变量。

如果你有一个直接的结构变量，那么就使用 . 操作员。例子：在这些例子中，我假设你在需要的时候已经分配了内存初始化结构。struct structName AStruct; var = AStruct.field;

在这些例子中，我假设你已经分配了内存 在需要的时候初始化了结构。