public function isValid($json=null) {
			if (empty($json) || ctype_space($json)) return false;
			json_decode($json);
			return (json_last_error() === JSON_ERROR_NONE);
		}
public function isValid($json=null) {
			if (empty($json) || ctype_space($json)) return false;
			json_decode($json);
			return (json_last_error() === JSON_ERROR_NONE);
		}
public function isValid ( $ json = null ) { if ( empty ( $ json ) || ctype_space ( $ json ) ) return false ; json_decode ( $ json ) ; return ( json_last_error ( ) === JSON_ERROR_NONE ) ; }
Determine is valid json or not

@param json is the json string

@return bool
Determine is valid json or not