Advanced Usage of Zend_Json
When encoding PHP objects as JSON, all public properties of that object will be encoded in a JSON object.
JSON does not allow object references, so care should be taken not to encode objects with recursive references. If you have issues with recursion, Zend_Json::encode() and Zend_Json_Encoder::encode() allow an optional second parameter to check for recursion; if an object is serialized twice, an exception will be thrown.
By default, Zend_Json will decode JSON objects as associative arrays. However, if you desire an object returned, you can specify this:
- // Decode JSON objects as PHP objects
- $phpNative = Zend_Json::decode($encodedValue, Zend_Json::TYPE_OBJECT);
Any objects thus decoded are returned as StdClass objects with properties corresponding to the key/value pairs in the JSON notation.
The recommendation of Zend Framework is that the individual developer should decide how to decode JSON objects. If an object of a specified type should be created, it can be created in the developer code and populated with the values decoded using Zend_Json.
Encoding PHP objects
If you are encoding PHP objects by default the encoding mechanism can only access public properties of these objects. When a method toJson() is implemented on an object to encode, Zend_Json calls this method and expects the object to return a JSON representation of its internal state.
Zend_Json has two different modes depending if ext/json is enabled in your PHP installation or not. If ext/json is installed by default json_encode() and json_decode() functions are used for encoding and decoding JSON. If ext/json is not installed a Zend Framework implementation in PHP code is used for en-/decoding. This is considerably slower than using the PHP extension, but behaves exactly the same.
Still sometimes you might want to use the internal encoder/decoder even if you have ext/json installed. You can achieve this by calling:
- Zend_Json::$useBuiltinEncoderDecoder = true: