Character added to JSON string - php

Question

I am using jQuery.parseJSON() to parse a response from jQuery.ajax() call to a PHP script.
The code works except on some server the characters 0000 are inserted at the start of the response string causing jQuery.parseJSON() to fail.
I can not figure how those character are being inserted, any ideas?
The characters are not in the PHP encoded string before echoing response.
Here is the scenario:
PHP script creates JSON string with:
$html = json_encode(myArrayOfValues);
echo $html
jQuery.ajax receives encoded string in:
....success: function(html, textStatus){
var response = jQuery.parseJSON(html);
....
To fixed the problem I added function that removes inserted characters and changed:
var response = jQuery.parseJSON(html);
to:
var response = parseJSONResponse(html);
Where:
function parseJSONResponse(html){
var foundChar = html.indexOf("{");
if(foundChar > 0 ){
html = html.substring(foundChar);
}
var response = jQuery.parseJSON(html);
return response;
}
Ultimately, it works but I'd like to know where the inserted characters are coming from and if there is a way to prevent them being inserted.

Answer 1

This could be a character encoding related issue. \u0000 is the NULL character. Although this could just be a coincidence it seems worth looking into.
I think the preferred character encoding for json is utf-8. Try adding this to the head of your calling page and see if it resolves the issue:
<meta charset="utf-8">
Hope that helps!