JsonArray::add()
Description
JsonArray::add()
appends a value to the array pointed by the JsonArray
.
If the JsonArray
is null, this function does nothing.
Signatures
bool add(bool value) const;
bool add(float value) const;
bool add(double value) const;
bool add(signed char value) const;
bool add(signed long value) const;
bool add(signed int value) const;
bool add(signed short value) const;
bool add(unsigned char value) const;
bool add(unsigned long value) const;
bool add(unsigned int value) const;
bool add(unsigned short value) const;
bool add(const char *value) const;
bool add(char *value) const;
bool add(const __FlashStringHelper *value) const;
bool add(const String &value) const;
bool add(const std::string &value) const;
bool add(JsonArray array) const;
bool add(JsonObject object) const;
bool add(JsonVariant variant) const;
Arguments
value
: the value to add to the array.
If you pass a JsonArray
, a JsonObject
, or a JsonVariant
, JsonArray::add()
makes a complete clone of the argument. In other words, the value is stored by copy, not by reference.
As usual, ArduinoJson makes a copy of a string in the JsonDocument
, except if it’s a const char*
.
Return value
JsonArray::add()
return a bool
that tells whether the operation was successful or not:
true
if the value was successfully added.false
if there was not enough memory in theJsonDocument
.
Remarks
ArduinoJson makes a copy of the string when you call this function with one of the following types:
char*
String
(orstd::string
)const __FlashStringHelper*
(i.e. Flash string)
This duplication consumes some space in the JsonDocument
; don’t forget to increase its capacity accordingly.
Example
StaticJsonDocument<200> doc;
JsonArray array = doc.to<JsonArray>();
array.add("hello");
array.add(3.14156);
serializeJson(doc, Serial);
will write
["hello",3.14156]