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>

const_iterator nlohmann::basic_json::cbegin ( ) const

inlinenoexcept

Returns a const iterator to the first element.

Illustration from cppreference.com

Returns

const iterator to the first element

Complexity

Constant.

Requirements

This function satisfies the Container requirements:

• The complexity is constant.
• Has the semantics of const_cast<const basic_json&>(*this).begin().

Example

The following code shows an example for cbegin.

#include <json.hpp>

using namespace nlohmann;

int main()
{
    // create an array value
    const json array = {1, 2, 3, 4, 5};

    // get am iterator to the first element
    json::const_iterator it = array.cbegin();

    // serialize the element that the iterator points to
    std::cout << *it << '\n';
}

Output:

1

The example code above can be translated with

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

.