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63 lines
2.0 KiB
63 lines
2.0 KiB
// ArduinoJson - https://arduinojson.org |
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// Copyright © 2014-2024, Benoit BLANCHON |
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// MIT License |
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// |
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// This example shows the different ways you can use Flash strings with |
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// ArduinoJson. |
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// |
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// Use Flash strings sparingly, because ArduinoJson duplicates them in the |
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// JsonDocument. Prefer plain old char*, as they are more efficient in term of |
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// code size, speed, and memory usage. |
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// |
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// https://arduinojson.org/v7/example/progmem/ |
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#include <ArduinoJson.h> |
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void setup() { |
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JsonDocument doc; |
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// You can use a Flash String as your JSON input. |
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// WARNING: the strings in the input will be duplicated in the JsonDocument. |
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deserializeJson(doc, F("{\"sensor\":\"gps\",\"time\":1351824120," |
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"\"data\":[48.756080,2.302038]}")); |
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// You can use a Flash String as a key to get a member from JsonDocument |
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// No duplication is done. |
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long time = doc[F("time")]; |
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// You can use a Flash String as a key to set a member of a JsonDocument |
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// WARNING: the content of the Flash String will be duplicated in the |
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// JsonDocument. |
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doc[F("time")] = time; |
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// You can set a Flash String as the content of a JsonVariant |
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// WARNING: the content of the Flash String will be duplicated in the |
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// JsonDocument. |
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doc["sensor"] = F("gps"); |
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// It works with serialized() too: |
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doc["sensor"] = serialized(F("\"gps\"")); |
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doc["sensor"] = serialized(F("\xA3gps"), 3); |
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// You can compare the content of a JsonVariant to a Flash String |
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if (doc["sensor"] == F("gps")) { |
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// ... |
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} |
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} |
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void loop() { |
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// not used in this example |
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} |
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// See also |
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// -------- |
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// |
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// https://arduinojson.org/ contains the documentation for all the functions |
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// used above. It also includes an FAQ that will help you solve any memory |
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// problem. |
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// |
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// The book "Mastering ArduinoJson" contains a quick C++ course that explains |
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// how your microcontroller stores strings in memory. It also tells why you |
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// should not abuse Flash strings with ArduinoJson. |
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// Learn more at https://arduinojson.org/book/ |
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// Use the coupon code TWENTY for a 20% discount ❤❤❤❤❤
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