PHP - json_decode from mysql

Question

I have an Android app, PHP page and MySql db.
The android app send a string parameter to the server, I use Gson so I know that the Json string is correct.
On server side I store that string of json as Text field.
On web client I take that field from my database and doing json_decode and receives a NULL.
Most of the site written by PHPMAKER 10 so I use it's database connection.

$result="";
$rs->MoveFirst();
if ($rs) {
    $result = $rs->fields[0];
}
$rs->Close();
$extras = json_decode($result, true);

I checked that json in Json validator and it looks fine.

Any ideas why I gets null? (maybe encoding)

EDIT: I did the following check:

echo "<script> var x = {$result}; console.log(x.length)</script>";

Chrome gave the following error:

Uncaught SyntaxError: Unexpected token ILLEGAL

EDIT 2: If I print that string echo $result and copy that to a variable it works.

The [`json_last_error_msg`](http://docs.php.net/manual/en/function.json-last-error-msg.php) function will give you to the error message. — Joni, Mar 31 '14 at 14:55
The error is just number 4 (JSON_ERROR_SYNTAX), but I already checked the json. — NickF, Mar 31 '14 at 15:00
Is the JSON string too long to check by hand? Start removing bits, or start by adding bits to `{}`, see which part the parser doesn't like. — Joni, Mar 31 '14 at 15:07
What is the result of `substr($result, 0, 3);`? Or did you already check the encoding? — Johann Bauer, Mar 31 '14 at 15:15

score 3 · Answer 1 · edited May 23 '17 at 12:01

That happened to me, when there was a UTF-8 BOM at the beginning of the JSON string. JSON is UTF-8 as default, so that BOM seems to be forbidden.

You could use this function to remove it:

//Remove UTF8 Bom

function remove_utf8_bom($text)
{
    $bom = pack('H*','EFBBBF');
    $text = preg_replace("/^$bom/", '', $text);
    return $text;
}

Taken from here: How to remove multiple UTF-8 BOM sequences before "<!DOCTYPE>"?

score 1 · Accepted Answer · answered Apr 02 '14 at 08:13

1

I soled the problem:
My json contained breaklines '/r' and '/r/n'.
After removing them everything was fine.

answered Apr 02 '14 at 08:13

NickF

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PHP - json_decode from mysql

2 Answers2