How to add data to a JSON file without completely overwriting it's current content? (php)

Question

Let's say I have a info.JSON file on my server, with the following data:

{"firstName":"John","age":"37"}

And in PHP, I want to add another key/value pair (somebody's middle name for example) to the info.JSON file. If I use the file_put_contents() function, that will overwrite the file completely. For example:

$middleName = array("middleName" => "Bill");
file_put_contents("info.json",json_encode($middleName));

The content of the info.JSON file would now be :

{"middleName":"Bill"}

How can I simply add more key/value pairs to an existing .JSON file without overwriting it?

Thanks.

`file_put_contents()` takes a 3rd argument which is called: **flags** and you can pass stuff like: `FILE_APPEND`. You have 1 guess left what this does :) (Read more about the function in the manual) — Rizier123, Aug 11 '15 at 23:19
`json_decode(file_get_contents('info.json'))`, then you'll have a PHP object you can deal with more easily and then write back into the file. — Don't Panic, Aug 11 '15 at 23:19
@Rizier123 It seems like just appending to the file would most likely break the JSON, what do you think? — Don't Panic, Aug 11 '15 at 23:20
Yeah, appending content to the file just adds it at the end of the file. And that's not properly formatted JSON. I'll try your solution, @Don't Panic . — bool3max, Aug 11 '15 at 23:23

score 0 · Answer 1 · answered Aug 11 '15 at 23:35

If you use json_decode($json,true) with the true flag so that it would come back as an associative array. Then you can add items using the array syntax and json_encode again before put in file .like this may be

$json=file_get_contents('path/to/your/file);
$temp = json_decode($json,true);
$temp['middleName'] ='Bill';
$json = json_encode($temp);
file_put_contents($json);

How to add data to a JSON file without completely overwriting it's current content? (php)

1 Answers1