JsonVariant::shallowCopy()
Description
JsonVariant::shallowCopy() includes the specified value without making a copy.
In a way, it’s the opposite of JsonVariant::set(), which makes a deep copy of the value.
JsonVariant::shallowCopy() allows you to embed a JsonDocument inside another without increasing the memory consumption.
This feature was added in ArduinoJson 6.20.0
Signatures
void shallowCopy(JsonVariantConst variant) const; Arguments
variant: the variant to link to.
Since JsonArray, JsonDocument, JsonObject, and JsonVariant convert to JsonVariantConst, you can pass any of these classes to JsonVariant::shallowCopy().
Example
void sendJsonRpcRequest(const char* method, JsonVariantConst params) { StaticJsonDocument<64> doc; doc["jsonrpc"] = "2.0"; doc["id"] = 1; doc["method"] = method; doc["params"].shallowCopy(params); serializeJson(doc, client); } 