allocator_type
array
array_t
at
at
at
at
back
back
basic_json
basic_json
basic_json
basic_json
basic_json
basic_json
basic_json
basic_json
basic_json
basic_json
basic_json
basic_json
basic_json
basic_json
basic_json
basic_json
basic_json
basic_json
basic_json
basic_json
basic_json
begin
begin
boolean_t
cbegin
cend
clear
const_pointer
const_reference
count
crbegin
crend
difference_type
dump
empty
end
end
erase
erase
erase
erase
find
find
front
front
get
get
get
get_allocator
get_ptr
get_ptr
is_array
is_boolean
is_discarded
is_null
is_number
is_number_float
is_number_integer
is_object
is_primitive
is_string
is_structured
max_size
number_float_t
number_integer_t
object
object_t
operator value_t
operator ValueType
operator!=
operator+=
operator+=
operator+=
operator<
operator<
operator<<
operator<<
operator<=
operator=
operator==
operator>
operator>=
operator>>
operator>>
operator[]
operator[]
operator[]
operator[]
operator[]
operator[]
parse
parse
parse_event_t
parser_callback_t
pointer
push_back
push_back
push_back
rbegin
rbegin
reference
rend
rend
size
size_type
string_t
swap
swap
swap
swap
type
value_t
value_type
~basic_json

template<template< typename U, typename V, typename...Args > class ObjectType = std::map, template< typename U, typename...Args > class ArrayType = std::vector, class StringType = std::string, class BooleanType = bool, class NumberIntegerType = int64_t, class NumberFloatType = double, template< typename U > class AllocatorType = std::allocator>

reference nlohmann::basic_json::operator+= | ( | const basic_json & | value | ) |

inline

add an object to an array Appends the given element value to the end of the JSON value. If the function is called on a JSON null value, an empty array is created before appending value.

Parameters

  value | the value to add to the JSON array

Exceptions

  std::domain_error | when called on a type other than JSON array or null

Complexity
  Amortized constant.

Example
  The example shows how `push_back` and `+=` can be used to add elements to a JSON array. Note how the `null` value was silently converted to a JSON array.
  #include <json.hpp>
  using namespace nlohmann;
  int main()
  {
  // create JSON values
  json array = {1, 2, 3, 4, 5};
  json null;
  // print values
  std::cout << array << '\n';
  std::cout << null << '\n';
  // add values
  array.push_back(6);
  array += 7;
  null += "first";
  null += "second";
  // print values
  std::cout << array << '\n';
  std::cout << null << '\n';
  }
  nlohmann::basic_json
  a class to store JSON values
  Definition: json.hpp:130
  nlohmann
  namespace for Niels Lohmann
  Definition: json.hpp:55
  nlohmann::basic_json::push_back
  void push_back(basic_json &&value)
  add an object to an array
  Definition: json.hpp:3615
  Output (play with this example online):

      [1,2,3,4,5]
      null
      [1,2,3,4,5,6,7]
      ["first","second"]

  The example code above can be translated with

      g++ -std=c++11 -Isrc doc/examples/push_back.cpp -o push_back