Problem json_encode utf-8 [duplicate]

Question

I have a problem with json_encode function with special characters.

For example I try this:

$string="Svrček";

echo "ENCODING=".mb_detect_encoding($string); //ENCODING=UTF-8

echo "JSON=".json_encode($string); //JSON="Svr\u010dek"

What can I do to display the string correctly, so JSON="Svrček"?

Thank you very much.

Answer 1

json_encode() is not actually outputting JSON* there. It’s outputting a javascript string. (It outputs JSON when you give it an object or an array to encode.) That’s fine, as a javascript string is what you want.

In javascript (and in JSON), č may be escaped as \u010d. The two are equivalent. So there’s nothing wrong with what json_encode() is doing. It should work fine. I’d be very surprised if this is actually causing you any form of problem. However, if the transfer is safely in a Unicode encoding (UTF-8, usually)†, there’s no need for it either. If you want to turn off the escaping, you can do so thus: json_encode('Svrček', JSON_UNESCAPED_UNICODE). Note that the flag JSON_UNESCAPED_UNICODE was introduced in PHP 5.4.0, and is unavailable in earlier versions.

By the way, contrary to what @onteria_ says, JSON does use UTF-8:

The character encoding of JSON text is always Unicode. UTF-8 is the only encoding that makes sense on the wire, but UTF-16 and UTF-32 are also permitted.

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* Or, at least, it's not outputting JSON as defined in RFC 4627. However, there are other definitions of JSON, by which scalar values are allowed.

† JSON may be in UTF-8, UTF-16LE, UTF-16BE, UFT-32LE, or UTF-32BE.