C结构和功能

Question

I'm new to C programming and I am trying to create a function that adds values to a structure but it does not return anything. This function is meant to allow the user to add records.

#include <stdio.h>
#include <string.h>
    
struct Produit {
    int Num;
    char Nom[50];
    char Description[100];
    float Prix;
} s[10];

void add(struct Produit s[],int n);
void display(struct Produit s[],int p,int n)

int main {
    add(s,1); 
    display(s,1);
    ++n;
}

void add(struct Produit s[], int n){
    again:
      printf("\nEntrez le nom du produit à ajouter:");
      scanf("%s",s[n].Nom);
      if(searchP(s,s[n].Nom,n)!=-1){
      printf("Déjà existant\n");goto again;
    }
    
    printf("Entrez la description :");
    scanf("%s",&s[n].Description);
    printf("Entrez le prix :");
    scanf("%f",&s[n].Prix);
}

void display(struct Produit s[],int p,int n) {
    printf("Nom du produit: ");
    puts(s[p-1].Nom);
    printf("Description: ");
    puts(s[p-1].Description);
    printf("Prix: %.1f", s[p-1].Prix);
    printf("\n");
}

When I run this it works fine but when I verify if the record that I've entered is is there I don't find anything. I try to display the record but it's empty. it returns this:

Entrez le nom du produit α ajouter:pen
Entrez la description :red
Entrez le prix :1.99
Nom du produit:
Description:
Prix: 0.0

can anyone tell what is wrong. thanks PS: The function SearchP is working fine in other parts of the code so I don't think it is the problem, but nonetheless here is it.

int searchP(struct Produit s[],char Name[], int n) {
    
    int found =-1,i;
    for (i = 0; i < n-1 && found==-1; i++)
    {
        if (strcmp(s[i].Nom,Name)==0) {
            found=i;
        }    
        else 
            found=-1;
  }

return found;
}

Answer 1

Here is a modified version of your code that works better but still needs some work.

As already commented you need a global counter for the s array (here: nbp ). There also one-off errors when searching into s .

#include <stdio.h>
#include <string.h>
    
struct Produit {
    int Num;
    char Nom[50];
    char Description[100];
    float Prix;
} s[10];

int nbp = 0;


void display(struct Produit s[],int p) {
    printf("Nom du produit: ");
    puts(s[p].Nom);
    printf("Description: ");
    puts(s[p].Description);
    printf("Prix: %.1f", s[p].Prix);
    printf("\n");
}


void add(struct Produit s[]);


int searchP(struct Produit s[],char Name[]) {
    
    int found =-1,i;
    for (i = 0; i < nbp && found==-1; i++)
    {
        if (strcmp(s[i].Nom,Name)==0) {
            found=i;
        }    
        else 
            found=-1;
  }
return found;
}

int main () {

    add(s); 
    display(s, 0);
    return 0;
}

void add(struct Produit s[]){
    again:
      printf("\nEntrez le nom du produit à ajouter:");
      scanf("%s",s[nbp].Nom);
      if(searchP(s,s[nbp].Nom)!=-1){
      printf("Déjà existant\n");goto again;
    }
    
    printf("Entrez la description :");
    scanf("%s",s[nbp].Description);
    printf("Entrez le prix :");
    scanf("%f",&s[nbp].Prix);
 

   nbp++;
}

Execution:

./myprog

Entrez le nom du produit à ajouter:Nom
Entrez la description :Desc
Entrez le prix :1
Nom du produit: Nom
Description: Desc
Prix: 1.0