PHP "pretty print" json_encode

Question

Possible Duplicate:
Pretty-Printing JSON with PHP

I'm working on a script that creates a JSON file. Right now I'm just using json_encode (PHP 5.2.x) to encode an array into JSON output. Then I print the returned value to a file and save it. Problem is that the client wants to be able to open these JSON files for readability, so I'd like to add line breaks in and "pretty print" the JSON output. Any ideas on how to do this? My only other alternative that I can see is to not use json_encode at all and just write the file contents manually and add in my own line breaks for each line.

Here's what I get:

{"product_name":"prod1","val1":1,"val2":8}

Here's what I want:

{
  "product_name":"prod1",
  "val1":1,
  "val2":8
}

I suppose I could also just replace every comma with a command followed by a \n, and same for the brackets... Thoughts?

Solution 1

PHP has JSON_PRETTY_PRINT option since 5.4.0 (release date 01-Mar-2012).

This should do the job:

$json = json_decode($string);
echo json_encode($json, JSON_PRETTY_PRINT);

See http://www.php.net/manual/en/function.json-encode.php

Note: Don't forget to echo "<pre>" before and "</pre>" after, if you're printing it in HTML to preserve formatting ;)

Solution 2

Hmmm $array = json_decode($json, true); will make your string an array which is easy to print nicely with print_r($array, true);

But if you really want to prettify your json... Check this out

Solution 3

Here's a function to pretty up your json: pretty_json

Solution 4

And for PHP 5.3, you can use this function, which can be embedded in a class or used in procedural style:

http://svn.kd2.org/svn/misc/libs/tools/json_readable_encode.php

View more solutions

Comments

[netcoder]

See this comment in the manual.

[Elangovan]

$jsonArr = '{"product_name":"prod1","val1":1,"val2":8}'; $jsonArr = json_decode($jsonArr); echo "<pre>";print_R($jsonArr);

[sg3s]

@Michael Mior you should see my debugging die die(print('<pre>'.print_r($var, true).'</pre>')) it prints almost anything :p

[Michael Mior]

I usually just view the source and go with var_dump, but whatever works :)

[emilyk]

Worked perfectly to simply copy and paste into my php file, especially since I didn't want to do all the work of upgrading to PHP 5.4 on my mac. Thanks.

[Nic Cottrell]

In PHP <5.4 replace JSON_PRETTY_PRINT with 128

[drzaus]

@NicCottrell doesn't work when i test it here sandbox.onlinephpfunctions.com/code/…

[petrkotek]

@drzaus works for me there - I can see each key of JSON on separate line (the PHP version used on that site has even JSON_PRETTY_PRINT defined.

[drzaus]

@beret ahh, I thought sharing it would retain the PHP setting -- change the php version to anything less than 5.4 and it should go back to "unformatted"

[petrkotek]

@drzaus Oh I see. I didn't look for the switch of PHP version. Yeah, apparently not only the constant has been added, but mainly the functionality. Makes sense.

[GisMofx]

Thank you for the <pre>json</pre> tip!

[kander]

Just wondering how brew install php54 is considered a lot of work. When doing development on a Mac, it's fairly likely you have homebrew installed...

[Octopus]

Instead of using "<pre>" tags (which will render your JSON invalid), you ought to use header("Content-Type: application/json") and then your browser will render it as plain text rather than markup.

[Marco]

Just use 128 as commented by @Nic Cottrell.