How to nest structures? - c

Question

typedef struct{
char name_cake[10];
char code_cake[10];
int stock_cake;
char about_cake[10];
char cake_taste[10];
}order;
typedef struct{
char name_cake[10];
char code_cake[10];
int stock_cake;
char about_cake[10];
char cake_taste[10];
}cake;
how to the contents of typedef struct become one? and I can invoke the command with
information.order.name_cake
information.cake.name_cake
for simply and not waste of words, thank

Answer 1

I would recommend to use the same struct for cake and order, there is no polymorphism in c

Answer 2

To access them in the way you like:
#include <stdio.h>
typedef struct{
char name_cake[10];
char code_cake[10];
int stock_cake;
char about_cake[10];
char cake_taste[10];
}order;
typedef struct{
char name_cake[10];
char code_cake[10];
int stock_cake;
char about_cake[10];
char cake_taste[10];
}cake;
typedef struct {
union {
order the_order;
cake the_cake;
}; // anonymous union
}information;
int main() {
order an_order = {"cakename", "code", 0, "about", "taste"};
information info = *((information*)&an_order);
printf("From order: %s\n", info.the_order.name_cake);
printf("From cake: %s\n", info.the_cake.name_cake);
return 0;
}
$ gcc -Wall ordercake.c
$ ./a.out
From order: cakename
From cake: cakename
$
In general you want to do object-oriented programming in C. Therefore, take a look at: How can I simulate OO-style polymorphism in C? (There is even a free book as pdf linked on how to do it.)
And now an example for a struct in a struct:
#include <stdio.h>
typedef struct{
char name_cake[10];
char code_cake[10];
}cake;
typedef struct{
cake the_cake; // the common part
char cake_extension[10]; // the new part, order is important
}extended_cake;
int main() {
extended_cake an_extended_cake = {{"cakename", "code"}, "extension"};
// now treat it as a cake
cake *a_normal_cake = (cake *)&an_extended_cake;
printf("From cake: %s\n", a_normal_cake->name_cake);
return 0;
}
$ gcc -Wall ordercake.c
$ ./a.out
From cake: cakename
$

Answer 3

Not sure what you're going to do, but you can simply nest structures like this:
struct foo {
order order;
cake cake;
}
If you want the contents of order and cake occupy the same memory space, you should use an anonymous union, as written above.

Answer 4

#include<stdio.h>
#include<string.h>
struct sports
{
char name[40];
int age;
/*nested structure*/
struct medicaltests
{
char isFit[1];
} med;/*nested object*/
};
int
main ()
{
struct sports sportobj;/*Declare object*/
strcpy (sportobj.name, "venkateshwar krishnan");
sportobj.age = 40;
strcpy (sportobj.med.isFit, "Y");
printf ("name of sportsman%s\n", sportobj.name);
printf ("IsFit %s", sportobj.med.isFit);
return 0;
}