PHP's json_encode does not escape all JSON control characters

Question

Is there any reasons why PHP\'s json_encode function does not escape all JSON control characters in a string?

For example let\'s take a string which spans two rows a

Answer 1

I don't fully understand how var_export works, so I will update if I run into trouble, but this seems to be working for me:

<script>
    window.things = JSON.parse(<?php var_export(json_encode($s)); ?>);
</script>

Answer 2

Maybe I'm blind, but in your example they ARE escaped. What about

<script type="text/javascript">

JSON.parse("<?php echo $s ?>");  // Will throw SyntaxError 

</script>

(note different quotes)

Answer 3

This is what I use personally and it's never not worked. Had similar problems originally.

Source script (ajax) will take an array and json_encode it. Example:

$return['value'] = 'test';
$return['value2'] = 'derp';

echo json_encode($return);

My javascript will make an AJAX call and get the echoed "json_encode($return)" as its input, and in the script I'll use the following:

myVar = jQuery.parseJSON(msg.replace(/"/ig,'"'));

with "msg" being the returned value. So, for you, something like...

var msg = '<?php echo $s ?>';
myVar = jQuery.parseJSON(msg.replace(/&quot;/ig,'"'));

...might work for you.

Answer 4

I still haven't figured out any solution without str_replace..

Try this code.

$json_encoded_string = json_encode(...);
$json_encoded_string = str_replace("\r", '\r', $json_encoded_string);
$json_encoded_string = str_replace("\n", '\n', $json_encoded_string);

Hope that helps...

Answer 5

function escapeJsonString($value) {
    # list from www.json.org: (\b backspace, \f formfeed)    
    $escapers =     array("\\",     "/",   "\"",  "\n",  "\r",  "\t", "\x08", "\x0c");
    $replacements = array("\\\\", "\\/", "\\\"", "\\n", "\\r", "\\t",  "\\f",  "\\b");
    $result = str_replace($escapers, $replacements, $value);
    return $result;
  }

I'm using the above function which escapes a backslash (must be first in the arrays) and should deal with formfeeds and backspaces (I don't think \f and \b are supported in PHP).

Answer 6

Just an addition to Greg's response: the output of json_encode() is already contained in double-quotes ("), so there is no need to surround them with quotes again:

<script type="text/javascript">
    JSON.parse(<?php echo $s ?>);
</script>