Question

If I want to send an array from PHP to JavaScript, I do something like this with PHP:

<?php
    $json=array();
    $json['datetime']="Something";
    $json['timestamp']="Something else"
    $encoded=json_encode($json);
    die($encoded);
?>

And this on jQuery/JavaScript (using Ajax):

...
success: function(response){
var chat = jQuery.parseJSON(response);
datetime=chat['datetime'];
timestamp=chat['timestamp'];
...

I was about wondering about doing the opposite.

In jQuery i have this array:

data_send['username']=$(".chat_username").val();
data_send['message']=$(".chat_message").val();

I want to encode this array as a JSON object, send this object via Ajax, and then take this object from $_POST/$_GET and decode it to an array.

How can I do this?

Answer 1

If you want to encode an array into JSON from Javascript you can use JSON.stringify(myarray).

However, you shouldn’t do that to send it to a PHP script.

jQuery has built in support for passing a map of key-value pairs in a POST method – just pass it as the data parameter in $.ajax() or as the second parameter to $.post().

jQuery will then correctly URI encode any unsafe characters that appear (whether in keys, or values), so in your case you can use:

var data_send = {
     username: $(".chat_username").val(),
     message:  $(".chat_message").val()
};
$.post(url, data_send, success_handler);

// or $.ajax({url: url, data: data_send, ... });

PHP then has built in support for reading that map – it’s $_POST:

<?php
    $username = $_POST['username'];
    $message  = $_POST['message'];
?>