JsonDocument::overflowed() tells whether the
JsonDocument was large enough to store all values.
This function was added in ArduinoJson 6.17.0
bool overflowed() const;
JsonDocument::overflowed() returns a
bool that tells if the memory pool overflowed
falsemeans that the memory pool was large enough, so all the values are present in the
truemeans that the memory pool was too small, so some values are missing from the