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78 lines
2.4 KiB
C++
78 lines
2.4 KiB
C++
// ArduinoJson - arduinojson.org
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// Copyright Benoit Blanchon 2014-2018
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// MIT License
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//
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// This example shows how to deserialize a JSON document with ArduinoJson.
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#include <ArduinoJson.h>
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void setup() {
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// Initialize serial port
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Serial.begin(9600);
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while (!Serial) continue;
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// Memory pool for JSON object tree.
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//
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// Inside the brackets, 200 is the size of the pool in bytes.
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// Don't forget to change this value to match your JSON document.
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// Use arduinojson.org/assistant to compute the capacity.
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StaticJsonBuffer<200> jsonBuffer;
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// StaticJsonBuffer allocates memory on the stack, it can be
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// replaced by DynamicJsonBuffer which allocates in the heap.
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//
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// DynamicJsonBuffer jsonBuffer(200);
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// JSON input string.
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//
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// It's better to use a char[] as shown here.
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// If you use a const char* or a String, ArduinoJson will
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// have to make a copy of the input in the JsonBuffer.
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char json[] =
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"{\"sensor\":\"gps\",\"time\":1351824120,\"data\":[48.756080,2.302038]}";
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// Root of the object tree.
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//
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// It's a reference to the JsonObject, the actual bytes are inside the
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// JsonBuffer with all the other nodes of the object tree.
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// Memory is freed when jsonBuffer goes out of scope.
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JsonObject& root = jsonBuffer.parseObject(json);
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// Test if parsing succeeds.
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if (!root.success()) {
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Serial.println("parseObject() failed");
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return;
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}
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// Fetch values.
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//
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// Most of the time, you can rely on the implicit casts.
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// In other case, you can do root["time"].as<long>();
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const char* sensor = root["sensor"];
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long time = root["time"];
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double latitude = root["data"][0];
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double longitude = root["data"][1];
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// Print values.
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Serial.println(sensor);
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Serial.println(time);
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Serial.println(latitude, 6);
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Serial.println(longitude, 6);
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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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// The website 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
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// deserialization problem.
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// Please check it out at: https://arduinojson.org/
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//
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// The book "Mastering ArduinoJson" contains a tutorial on deserialization.
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// It begins with a simple example, like the one above, and then adds more
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// features like deserializing directly from a file or an HTTP request.
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// Please check it out at: https://arduinojson.org/book/
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