我如何在C中的Malloc中启动多个字符串

Question

我正在尝试学习C，并且我有一个使用Malloc和struct的Asignment，并且我将其打印出了队列编号，但字符串不会打印。我已经附上了印刷品的图片，但是只有在评论strcpy并且无法弄清楚时才起作用。

谁能解释我做错了什么，该怎么办？

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

struct car
{
    int queue;
    char *Regnr;
    char *Manufactor;
    char *WashType;
    char *CarId;
    struct car *next;
};

typedef struct car CarWash;

/* print the list out from ... */
void printlist (CarWash * head)
{
    CarWash *temp = head;

    while (temp != NULL)
    {
        printf ("%d\t\t %s\t\t %s\t\t %s\t \n", temp->queue, temp->Regnr,
                temp->Manufactor, temp->WashType);
        temp = temp->next;
    }
    printf ("\n");
};

CarWash *create_new_queue(int val,char CarId)
{
CarWash *result = malloc (sizeof (CarWash));
char strcpy(char Regnr, char CarId);
result->Regnr = CarId;
result->queue = val;

result->next = NULL;
return result;
 };

编辑

int
main ()
{
  int queue;
  char Regnr[10];
  char Manufactor[10];
  char WashType[10];
  char CarId[10];



  CarWash *head;
  CarWash *tempB;


  FILE *fp;
  fp = fopen ("Car wash.txt", "r");
  
  fscanf (fp, "%d%s%s%s", &queue, Regnr, Manufactor, WashType);
  
  fclose (fp);

  printf (" \n");       //voodoo to show my printlist

  tempB = create_new_queue (queue, Regnr);
  head = tempB;

  printf ("%s\t %s\t\t %s\t %s\n", "kø plads", "Regnr", "Manufactor",
      "vaske type");

  printlist (head);
  return 0;

}

编辑的

印刷内容：

Answer 1

您可能想要这个：

struct car
{
    int queue;
    char Regnr[10];       // don't declare pointers but arrays
    char Manufactor[10];
    char WashType[10];
    char CarId[10];
    struct car *next;
};

校正的create_new_queue函数：

CarWash* create_new_queue(int val, char *CarId)  // add the *, CarId is not a char
{
  CarWash* result = malloc(sizeof(CarWash));
  strcpy(result->Regnr, CarId);   // actually call strcpy
  result->queue = val;
  result->next = NULL;
  return result;
};

我建议您阅读有关指针的章节以及与学习材料中的字符串有关的章节。