将结构传递给函数c

Question

I'm trying to wite a code that would create an array of structures. I'm still at the early stages where I am trying to pass the structure to a function and though I figured pointer would have to be utitlized, I just can't figure out how to do it the correctly. Here's my code below.

#include <stdio.h>

struct age{
    int num;
};

struct name{
    char fname [15];
    char lname[15];
    struct age nameAge;
};

void input(struct name *info[]);

int main (void){
char choice;
char ans;
int i;
struct name record[10];
do{
    printf("M E N U");
    printf("\n\n[I]nput\n[D]isplay\n[S]earch\n[Q]uit");
    printf("\n\nEnter choice: ");
    choice=tolower(getche());
    system("cls");

    switch (choice){
        case 'i': input(&record[]);
                  i++;
                break;
        case 'd': //function here
                break;
        case 's': //fucntion here
                break;
        case 'q': printf("The program will now close.");
                break;
        default: printf("Invalid character. Try again");
                break;
        }

    getch();
    system("cls");

   }while (choice!='q');
return 0;
}

void input(struct name *info[]){
//codes here
}

Answer 1

Keep in mind that The name of an array "decays" to a pointer to its first element . So, in your case, just use record to pass the "array" (You can't really pass an array) to the function. You also need to change the function argument type to struct info* as record is of type struct info* .

Here is the working code with the changes commented:

#include <stdio.h>

struct age{
    int num;
};

struct name{
    char fname[15];
    char lname[15];
    struct age nameAge;
};

/*void input(struct name *info[]);  Note the change in the declaration */
void input(struct name *info);

int main (void){
    char choice;
    char ans;
    int i;
    struct name record[10];
    do{
        printf("M E N U");
        printf("\n\n[I]nput\n[D]isplay\n[S]earch\n[Q]uit");
        printf("\n\nEnter choice: ");
        choice=tolower(getche());
        system("cls");

        switch (choice){
            case 'i': input(record); /* Note the change here as well */
                      i++;
                    break;
            case 'd': //function here
                    break;
            case 's': //fucntion here
                    break;
            case 'q': printf("The program will now close.");
                    break;
            default: printf("Invalid character. Try again");
                    break;
            }

        getch();
        system("cls");

       }while (choice!='q');
    return 0;
}

void input(struct name *info){ /* Note the change here in the function definition too */
    //codes here
}

Answer 2

Change the function definition and implementation and the function call like this (if you want to use arrays)

void input(struct name info[]);
...
           input(record);

Or using pointer (also works with arrays as arguments)

void input(struct name *info);
...
           input(record);

Answer 3

You don't want to do this void input(struct name *info[]); for your input function. You want to pass a reference to one of the info structs in the array to the function since you only will ever edit one info at a time.

So your altered function would be void input(struct name *info); and you would call it using input(&record[i]); which gives the address of record i. You also need to initialize i as you never set it to 0, but incitement it.

Answer 4

another suggestion for you....

use a record counter.... - you have to call the routine for each time you want to add a record. (I have editted the code so you send the routine a pointer to a single record structure, rather than pass the whole structure).

#include <stdio.h>

struct age{
    int num;
};

struct name{
    char fname [15];
    char lname[15];
    struct age nameAge;
};

// void input(struct name *info[]);
void input(struct name *info);

int main (void){
char choice;
char ans;
int i;

int n_records=0;

struct name record[10];
do{
    printf("M E N U");
    printf("\n\n[I]nput\n[D]isplay\n[S]earch\n[Q]uit");
    printf("\n\nEnter choice: ");
    choice=tolower(getche());
    system("cls");

    switch (choice){
        case 'i': input(&record[n_records]);
                  i++;
                  nrecords++;
                break;
        case 'd': //function here
                break;
        case 's': //fucntion here
                break;
        case 'q': printf("The program will now close.");
                break;
        default: printf("Invalid character. Try again");
                break;
        }

    getch();
    system("cls");

   }while (choice!='q');
return 0;
}

// void input(struct name *info[]){
void input(struct name *info){
//codes here
}