Tasmota/lib/ArduinoJson-5.13.4/examples/ProgmemExample/ProgmemExample.ino

71 lines
2.1 KiB
C++

// ArduinoJson - arduinojson.org
// Copyright Benoit Blanchon 2014-2018
// MIT License
//
// This example shows the different ways you can use Flash strings with
// ArduinoJson.
//
// Use Flash strings sparingly, because ArduinoJson duplicates them in the
// JsonBuffer. Prefer plain old char*, as they are more efficient in term of
// code size, speed, and memory usage.
#include <ArduinoJson.h>
void setup() {
#ifdef PROGMEM // <- check that Flash strings are supported
DynamicJsonBuffer jsonBuffer;
// You can use a Flash String as your JSON input.
// WARNING: the content of the Flash String will be duplicated in the
// JsonBuffer.
JsonObject& root =
jsonBuffer.parseObject(F("{\"sensor\":\"gps\",\"time\":1351824120,"
"\"data\":[48.756080,2.302038]}"));
// You can use a Flash String to get an element of a JsonObject
// No duplication is done.
long time = root[F("time")];
// You can use a Flash String to set an element of a JsonObject
// WARNING: the content of the Flash String will be duplicated in the
// JsonBuffer.
root[F("time")] = time;
// You can set a Flash String to a JsonObject or JsonArray:
// WARNING: the content of the Flash String will be duplicated in the
// JsonBuffer.
root["sensor"] = F("gps");
// It works with RawJson too:
root["sensor"] = RawJson(F("\"gps\""));
// You can compare the content of a JsonVariant to a Flash String
if (root["sensor"] == F("gps")) {
// ...
}
#else
#warning PROGMEM is not supported on this platform
#endif
}
void loop() {
// not used in this example
}
// See also
// --------
//
// https://arduinojson.org/ contains the documentation for all the functions
// used above. It also includes an FAQ that will help you solve any memory
// problem.
//
// The book "Mastering ArduinoJson" contains a quick C++ course that explains
// how your microcontroller stores strings in memory. It also tells why you
// should not abuse Flash strings with ArduinoJson.
// Learn more at https://arduinojson.org/book/
// Use the coupon code TWENTY for a 20% discount ❤❤❤❤❤