How do you store a user input after calling a void function in C?-CodePudding

Issue: I am writing this program which allows users to enter their name and school details via fgets() method in a void function after being called from the int function, how do i make sure that the array in this void function is a global array which then allows me to call another function called list users that lists all the user details?

int main(){

int choice, userEnd =1;
printf("1: list user details\n");
printf("2: add user details \n");
printf("3: end the programme\n");

while(userEnd)
{
    printf("Enter your choice: \n");
    scanf("%d",&choice);
    if(choice==1){
        listUsers();
    }
    if(choice ==2){
        addUsers();
    }
    if(choice ==3){
        userEnd =0;
    }
    
}
return 0;
}

void addUsers(){
    int length = 100;
    char userName[length];
    char className[length];
  
    printf("Enter user name\n");
    fgets(userName,size,stdin);
    printf("Enter className:\n");
    fgets(className,size,stdin);
    printf("User added\n");
    
}

void listUsers(){

/*if addUsers array is empty, print "empty", else print all user details from addUsers.*/
printf("your name is %s, your class is %s",userName, userSize)

}

CodePudding user response：

If you want to declare a global array, you have to declare it outside the functions scope, so in your case:

/* global array, declared in the global scope */
array_type array[ELEMENTS];

int main () {

}

void addUsers () {

}

void listUsers () {

}

Using that setup you will be able to manipulate the array from every function.

But, as it has been said in the comments, you should not use global variables/arrays in this case. Instead, you should use return values and arguments.

CodePudding user response：

Something like that will do! Note that this code is still a non- working copy of what you want to do but with a few little touches, it should work fine.

/* Global vars */
const int length = 100;
char *userName[length]; // array of strings
char *className[length];

/* Keep track of number of users */
int userCount = 0;

int main(){

    int choice, userEnd =1;
    printf("1: list user details\n");
    printf("2: add user details \n");
    printf("3: end the programme\n");

    while(userEnd)
    {
        printf("Enter your choice: \n");
        scanf("%d",&choice);
        if(choice==1){
            listUsers();
        }
        if(choice ==2){
            addUsers();
            userCount  ;
        }
        if(choice ==3){
            userEnd =0;
        }
        
    }
    return 0;
}

void addUsers(){
    // TODO: make sure userCount doesn't exceed the length
    // TODO: define size
    printf("Enter user name\n");
    fgets(userName[userCount],size,stdin);
    printf("Enter className:\n");
    fgets(className[userCount],size,stdin);
    printf("User added\n");
    
}

void listUsers(){
    int i;

    /*if addUsers array is empty, print "empty", else print all user details from addUsers.*/
    if (userCount > 0)
    {
        for (i = 0, i < userCount, i  )
        {
            printf("your name is %s, your class is %s",userName[i], className[i]);
        }
    }
    else
    {
        printf("No users registered");
    }

}