JsonDocument::memoryUsage()
Description
JsonDocument::memoryUsage() the number of bytes used in the JsonDocument.
Unlike JsonArray::memoryUsage(), JsonObject::memoryUsage(), and JsonVariant::memoryUsage(), the result includes leaked memory.
Use this function at design time to measure the required capacity for the JsonDocument.
Signature
size_t memoryUsage() const;
Example
char json[] = "{\"a\":1,\"b\":2}";
StaticJsonDocument<200> doc;
deserializeJson(doc, json);
JsonObject object = doc.as<JsonObject>();
object.remove("b"); // remove last member to show the effect of a leak
Serial.println(object.memoryUsage()); // 10 on AVR
Serial.println(doc.memoryUsage()); // 16 on AVR
