ArduinoJson is a C++ JSON library for Arduino and IoT (Internet Of Things).
Features
JSON decoding (comments are supported)
JSON encoding (with optional indentation)
Elegant API, easy to use
Fixed memory allocation (zero malloc)
No data duplication (zero copy)
Portable (written in C++98, can be used in any C++ project)
Self-contained (no external dependency)
Small footprint
Input and output streams
Compatibility
ArduinoJson works on the following hardware:
RedBearLab boards: BLE Nano, BLE Mini, WiFi Micro, LOLIN32…
Teensy boards
Intel boards: Edison, Galileo…
Texas Instruments boards: MSP430…
ArduinoJson compiles with zero warning on the following compilers, IDEs, and platforms:
Quickstart
Deserialization
Here is a program that parses a JSON document with ArduinoJson.
char json[] = "{\"sensor\":\"gps\",\"time\":1351824120,\"data\":[48.756080,2.302038]}";
StaticJsonBuffer<200> jsonBuffer;
JsonObject& root = jsonBuffer.parseObject(json);
const char* sensor = root["sensor"];
long time = root["time"];
double latitude = root["data"][0];
double longitude = root["data"][1];
See the tutorial on arduinojson.org
Serialization
Here is a program that generates a JSON document with ArduinoJson:
StaticJsonBuffer<200> jsonBuffer;
JsonObject& root = jsonBuffer.createObject();
root["sensor"] = "gps";
root["time"] = 1351824120;
JsonArray& data = root.createNestedArray("data");
data.add(48.756080);
data.add(2.302038);
root.printTo(Serial);
// This prints:
// {"sensor":"gps","time":1351824120,"data":[48.756080,2.302038]}
See the tutorial on arduinojson.org
Documentation
The documentation is available on arduinojson.org, here are some shortcuts:
The Examples show how to use the library in various situations.
The API Reference contains the description of each class and function.
The FAQ has the answer to virtually every question.
The ArduinoJson Assistant writes programs for you!
Do you like this library? Please star this project on GitHub!
What? You don’t like it but you love it? We don’t take donations anymore, but we sell a book, so you can help and learn at the same time!