php - How to determine whether a string is valid JSON?

Question

Does anyone know of a robust (and bullet proof) is_JSON function snippet for PHP? I (obviously) have a situation where I need to know if a string is JSON or not.

Hmm, perhaps run it through a JSONLint request/response, but that seems a bit overkill.

Answer 1

If you are using the built in json_decode PHP function, json_last_error returns the last error (e.g. JSON_ERROR_SYNTAX when your string wasn't JSON).

Usually json_decode returns null anyway.