Description

Sets the value at specified index.

Signatures

bool set(size_t index, bool value);
bool set(size_t index, double value);
bool set(size_t index, float value);
bool set(size_t index, signed char value);
bool set(size_t index, signed int value);
bool set(size_t index, signed long value);
bool set(size_t index, signed short value);
bool set(size_t index, unsigned char value);
bool set(size_t index, unsigned int value);
bool set(size_t index, unsigned long value);
bool set(size_t index, unsigned short value);
bool set(size_t index, const char *value);
bool set(size_t index, char *value); // see Remarks
bool set(size_t index, const std::string &value); // see Remarks
bool set(size_t index, const String &value); // see Remarks
bool set(size_t index, const __FlashStringHelper *value); // see Remarks
bool set(size_t index, JsonArray &array);
bool set(size_t index, JsonObject &object);
bool set(size_t index, const JsonVariant &value);

Arguments

index: the index in the array (starting from 0).

value: the value to set.

Return value

true if allocation succeeded.

false if there was not enough space left in the JsonBuffer, this can only happen when value needs to be copied (see below).

Remarks

ArduinoJson make a copy of the string when you call this function with one of the following types:

  • char*
  • String (or std::string)
  • const __FlashStringHelper * (i.e. Flash string)

This duplication causes the JsonBuffer to grow. The memory allocated for the copy will only be freed when the whole JsonBuffer is discarded.

Note that the rules changed in version 5.13.

Example

StaticJsonBuffer<200> jsonBuffer;
JsonArray& array = jsonBuffer.createArray();

// increase the size of the array
array.add(666);
array.add(666);

// replace the values
array.set(0, "hello");
array.add(1, 3.14156);

// serialize
array.printTo(Serial);

will write

["hello",3.14156]

See also