php json_encode有时返回0，零值[重复]

something is going wrong , im saving json_encode response in mysql db. it sometimes saving 0 value.im 100% sure that my json_encode function does not receive 0 as a parameter because it always get empty array or associated array, so there is no any chance to receive 0 in parameter.

Problem is that why json_encode returns 0 value sometimes. i have column type longtext in db table where im saving its response. is it issue with character types? like UTF8 or non UTF8?

Here is a code snippet:

$jsonPayload = [];

if (isset($obj['answer']) && (!empty($obj['answer']) || $obj['answer'] == 0)) {
       $jsonPayload[$form_fields[$i]->id] = $obj;         
}

return json_encode($jsonPayload);

</div>

use

json_encode($jsonPayload,JSON_UNESCAPED_SLASHES);

Probably it will work.