ArduinoJson: F.A.Q

What's the best way to use the library?

Here is the canonical example for serializing and deserializing with ArduinoJson.

By following this example, you are making the best usage of your memory and you maintain a good software design.

struct SensorData {
   const char* name;
   int time;
   float value;


bool deserialize(SensorData& data, char* json)
    StaticJsonBuffer<SENSORDATA_JSON_SIZE> jsonBuffer;
    JsonObject& root = jsonBuffer.parseObject(json); = root["name"];
    data.time = root["time"];
    data.value = root["value"];
    return root.success();

void serialize(const SensorData& data, char* json, size_t maxSize)
    StaticJsonBuffer<SENSORDATA_JSON_SIZE> jsonBuffer;
    JsonObject& root = jsonBuffer.createObject();
    root["name"] =;
    root["time"] = data.time;
    root["value"] = data.value;
    root.printTo(json, maxSize);

As you can see the StaticJsonBuffer is kept in memory as short as possible, so that the remain of your program is unaffected by the JSON serialization.

Also you can see that neither JsonArray nor JsonObject leak out of the serialization code. This maintain a good isolation and reduce the coupling with the library.

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