How to Convert JSON file into CSV in PHP ?

In this article, we are going to see how to convert JSON data into a CSV file using PHP.

JSON (JavaScript Object Notation) is a dictionary-like notation that can be used to structuring data. It is stored with the extension .json, for example – geeksforgeeks.json

On the other hand, CSV (or Comma Separated Value) files represent data in a tabular format, with several rows and columns. An example of a CSV file can be an Excel Spreadsheet. These files have the extension of .csv, for example – geeksforgeeks.csv.

Requirements: XAMPP Server

Structure of JSON:

[{
    "data1": "value1", 
    "data2": "value2", 
    ..., 
    "data n": "value n"
}]

Example:

[{
    "student": "sravan kumar",
    "age": 22,
    "subject": "java"
}]

Used Methods:

1. json_decode() Method: This function is used to decode or convert a JSON object to a PHP object.

   Syntax:

   json_decode( string, assoc )
   
   
   Example:
   
   $jsondata = '[{
       "student": "sravan kumar",
       "age": 22,
       "subject": "java"
   },
   {
       "student": "ojaswi",
       "age": 21,
       "subject": "java"
   },
   { 
       "student": "rohith",
       "age": 22,
       "subject": "dbms"
   },
   {
       "student": "bobby",
       "age": 22,
       "subject": "sql"
   }]';
   
   // Decode the json data and convert it
   // into an associative array
   $jsonans = json_decode($jsondata, true);
   
   

2. fopen() Method: It is used to open a file.

   Syntax:

   fopen( filename, file_mode )

   Example:

   // File pointer in writable mode
   $file_pointer = fopen($csv, 'w');
   

3. fclose() Method: It is used to close the file.

   Syntax:

   fclose( $file_pointer );

   Example:

   fclose( $file_pointer );

4. fputcsv() Method: It is used to place the data into CSV file.

   Syntax:

   fputcsv( file, fields )

   Example:

   fputcsv( $file_pointer, $i );

Steps to Run:

• Start XAMPP server

• Open notepad and type the following code in json.php and place it under htdocs folder.

PHP code:

PHP

<?php

// Student JSON data
$jsondata =
  '[
   {"student":"sravan kumar","age":22,"subject":"java"},
   {"student":"ojaswi","age":21,"subject":"java"},
   {"student":"rohith","age":22,"subject":"dbms"},
   {"student":"bobby","age":22,"subject":"sql"}]';

// Decode json data and convert it
// into an associative array
$jsonans = json_decode($jsondata, true);

// CSV file name => geeks.csv
$csv = 'geeks.csv';

// File pointer in writable mode
$file_pointer = fopen($csv, 'w');

// Traverse through the associative
// array using for each loop
foreach($jsonans as $i){

    // Write the data to the CSV file
    fputcsv($file_pointer, $i);
}

// Close the file pointer.
fclose($file_pointer);

?>

Output: Type localhost/json.php in your browser. You can see the CSV file is created with the file name as geeks.csv