➕ JSON 转 C++ 结构体JSON to C++ Struct

使用说明与常见问题How-to & FAQ

「JSON 转 C++ 结构体」是什么？What is the JSON to C++ Struct tool?

把 JSON 转换成 C++ 结构体：std::string、std::vector、std::optional 等现代 C++17 类型，嵌套结构按依赖顺序输出，可选生成 nlohmann/json 的 from_json / to_json 序列化函数。Turn JSON into C++ structs using modern C++17 types (std::string, std::vector, std::optional), ordered by dependency, with optional nlohmann/json from_json / to_json functions.

如何使用「JSON 转 C++ 结构体」？How do I use the JSON to C++ Struct?

粘贴 JSON 并填写根结构体名，下方生成可直接编译的头文件。可能缺失或为 null 的字段会用 std::optional；勾选 nlohmann/json 后还会生成序列化函数，直接 j.get() 即可解析。Paste JSON and set the root struct name to get a ready-to-compile header. Fields that may be missing or null use std::optional; with nlohmann/json enabled you also get serialization functions, so j.get() just works.

生成的代码需要什么编译器？Which compiler standard is needed?

代码使用 std::optional 和 if 初始化语句，需要 C++17 或更高（如 g++ -std=c++17）。nlohmann/json 是单头文件库，可以通过 vcpkg、Conan 或直接下载 json.hpp 引入。The code uses std::optional and if-with-initializer, so it needs C++17 or later (e.g. g++ -std=c++17). nlohmann/json is a single-header library available via vcpkg, Conan or by downloading json.hpp.

为什么结构体顺序和 JSON 里不一样？Why is the struct order different?

C++ 要求先定义被使用的类型，所以嵌套的子结构体会排在父结构体前面输出。C++ requires a type to be defined before it is used by value, so nested structs are emitted before their parents.

「JSON 转 C++ 结构体」免费吗？数据会上传吗？Is the JSON to C++ Struct free? Is my data uploaded?

「JSON 转 C++ 结构体」完全免费，无需注册或安装，手机和电脑都能用；所有处理都在你的浏览器本地完成，输入的内容和文件不会上传到服务器。The JSON to C++ Struct is completely free with no sign-up or install and works on phones and desktops; everything runs locally in your browser and nothing you enter is uploaded.