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i am using frozen.h for json files .. I want to read the book array info from .json file into an array of structs
***********problem 1**********

.. struct book has a nested struct date which I want to access in .json file .. but the library won't allow me .. if you know a solution to my problem with frozen.h OR you'd recommend another library for json files in C that supports the following feature:
* read/write from/into json file and array of structs that has nested structs
*scans a string directly into C variables
* prints C variables directly into an output stream
* modifies an existing JSON string

*********problem 2**********

when storing the book title in array[0].title for example the saved string is Automation only not Automation and Robotics

What I have tried:

#include <stdio.h>
#include "frozen.h"
#include <stdlib.h>
#include <string.h>
typedef struct

    int day;
    int month;
    int year;
} dateStruct;

typedef struct

    char title[10];
    char author[10];
    char publisher[10];
    char ISBN[10];
    dateStruct date;
    int copies;
    int current;
    int times_borrowed;
} book;
int main()
{   book array[3];

  char *content = json_fread("tmp.json");
//tmp.json exists near main.c 
//and written in json format
  int i, value, len = strlen(content);
  struct json_token t;
  for (i = 0; json_scanf_array_elem(content, len, ".book", i, &t) > 0; i++) {
    json_scanf(t.ptr, t.len, "{title: %s}", &(ar[i].title));

    return 0;

==========the json file ============
"book": [

"title": "Automation And Robotics",
"author": "Miltiadis Boboulos",
"publisher": "Academic Studies Press",
"ISBN": "978-87-7681-696-4",
"date" : [
} ],


"title": "engineering",
"author": "Abimbola Windapo",
"publisher": "Allen & Unwin",
"ISBN": "978-87-403-0362-9",
"date" : [
} ],


Updated 12-Jan-18 4:48am
Richard MacCutchan 21-Dec-17 3:48am    
frozen.h is a C/C++ header file. What actual library are you trying to use, and what does the documentation say?

1 solution

you arent using the library in the correct way. Take a look at the sample code on Github to understand it. The key fuction is json_scanf which can have different parameter like a function pointer to scan subobjects. The rest is some nesting of the code to match your data structure.
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