JsonVariant::getOrAddMember()

Description

JsonVariant::getOrAddMember() reproduces JsonObject::getOrAddMember(); it only works if the JsonVariant points an object.

• If the JsonVariant points to an object, JsonVariant::getOrAddMember() gets the value associated with the specified key. If the key is not present in the object, this function adds a new key-value pair to the object.

• If the JsonVariant doesn’t point to an object, JsonVariant::getOrAddMember() does nothing.

Instead of this function, you can use JsonVariant::operator[] which offers a more intuitive syntax.

Signatures

JsonVariant getOrAddMember(const char* key) const;
JsonVariant getOrAddMember(const String& key) const;
JsonVariant getOrAddMember(const std::string& key) const;
JsonVariant getOrAddMember(std::string_view key) const;  // 🆕 (added in 6.18.1)
JsonVariant getOrAddMember(const __FlashStringHelper* key) const;

Arguments

key: the key of the value in the object.

As usual, ArduinoJson makes a copy of the key in the JsonDocument, except if it’s a const char*.

Return value

If the key is already present in the object, this function returns a JsonVariant that points to the associated value.

If the key is not present in the object, this function adds a new key-value pair to the object and returns a JsonVariant that points to the value. The returned JsonVariant could be null if there were not enough room in the JsonDocument.

See also

• JsonVariant::operator[]
• JsonObject::getOrAddMember()
• JsonVariant::getMember()