How to Convert JSON file into CSV in PHP ?

Last Updated : 13 Apr, 2021

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:

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);

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');

fclose() Method: It is used to close the file.
Syntax:
```
fclose( $file_pointer );
```
Example:
```
fclose( $file_pointer );
```
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);

?>