Skip to content

# nlohmann::ordered_json

    using ordered_json = basic_json<ordered_map>;

This type preserves the insertion order of object keys.

## Examples

Example

The example below demonstrates how `ordered_json` preserves the insertion order of object keys.

    #include <iostream>
    #include <nlohmann/json.hpp>

    using ordered_json = nlohmann::ordered_json;

    int main()
    {
        ordered_json j;
        j["one"] = 1;
        j["two"] = 2;
        j["three"] = 3;

        std::cout << j.dump(2) << '\n';
    }

Output:

    {
      "one": 1,
      "two": 2,
      "three": 3
    }

## See also

- ordered_map
- Object Order

## Version history

Since version 3.9.0.

Last update: May 17, 2022
Back to top