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Updated FAQ (markdown)

Benoît Blanchon
2016-08-29 19:10:45 +02:00
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FAQ.md

@@ -10,6 +10,7 @@
* [How to reuse a `JsonBuffer`?](#how-to-reuse-a-jsonbuffer) * [How to reuse a `JsonBuffer`?](#how-to-reuse-a-jsonbuffer)
* [What's the best way to use the library?](#whats-the-best-way-to-use-the-library) * [What's the best way to use the library?](#whats-the-best-way-to-use-the-library)
* [How to write a function that works with both `JsonArray` and `JsonObject`?](#how-to-write-a-function-that-works-with-both-jsonarray-and-jsonobject) * [How to write a function that works with both `JsonArray` and `JsonObject`?](#how-to-write-a-function-that-works-with-both-jsonarray-and-jsonobject)
* [How to assign a `JsonArray` or `JsonObject`?](#how-to-assign-a-jsonarray-or-jsonobject)
* [Part 2 - Serialization questions](#part-2---serialization-questions) * [Part 2 - Serialization questions](#part-2---serialization-questions)
* [How to compute the JSON length?](#how-to-compute-the-json-length) * [How to compute the JSON length?](#how-to-compute-the-json-length)
* [How to create complex nested objects?](#how-to-create-complex-nested-objects) * [How to create complex nested objects?](#how-to-create-complex-nested-objects)
@@ -294,7 +295,30 @@ void myFunction(JsonVariant variant)
See issue [#195](https://github.com/bblanchon/ArduinoJson/issues/195) and [#196](https://github.com/bblanchon/ArduinoJson/issues/196) See issue [#195](https://github.com/bblanchon/ArduinoJson/issues/195) and [#196](https://github.com/bblanchon/ArduinoJson/issues/196)
### How to assign a `JsonArray` or `JsonObject`?
If you try to reassign a `JsonArray&` or a `JsonObject&`, you'll have the following error:
```
error: use of deleted function 'ArduinoJson::JsonArray& ArduinoJson::JsonArray::operator=(const ArduinoJson::JsonArray&)'
error: use of deleted function 'ArduinoJson::JsonObject& ArduinoJson::JsonObject::operator=(const ArduinoJson::JsonObject&)'
```
Indeed, you cannot reassign a `JsonObject&`.
One solution is to use a pointer instead.
```c++
JsonObject* myObject = &root["myObject"].as<JsonObject>();
```
You can also use a `JsonVariant` which will act as a wrapper around the pointer.
```c++
JsonVariant myObject = root["myObject"];
```
See issues [#341](https://github.com/bblanchon/ArduinoJson/issues/341) and [#343](https://github.com/bblanchon/ArduinoJson/issues/343).
## Part 2 - Serialization questions ## Part 2 - Serialization questions