🟣 JSON 转 Kotlin 数据类JSON to Kotlin Data Class

使用说明与常见问题How-to & FAQ

「JSON 转 Kotlin 数据类」是什么？What is the JSON to Kotlin Data Class tool?

粘贴 JSON 自动生成 Kotlin data class，可选 kotlinx.serialization、Gson 或 Moshi 注解；嵌套对象和数组生成独立类，缺失或为 null 的字段自动变成可空类型。Paste JSON to generate Kotlin data classes with optional kotlinx.serialization, Gson or Moshi annotations; nested objects and arrays become their own classes and missing or null fields become nullable.

如何使用「JSON 转 Kotlin 数据类」？How do I use the JSON to Kotlin Data Class?

把 JSON 粘贴到上方输入框，选择注解风格并填写根类名，下方会实时生成 Kotlin 代码，点击「复制结果」即可。例如 {"user_name":"Alice"} 会生成 val userName: String，并带上 @SerialName("user_name")。Paste JSON into the input, pick an annotation style and root class name, and the Kotlin code appears below — click "Copy result". For example {"user_name":"Alice"} becomes val userName: String with @SerialName("user_name").

字段名里的下划线会怎么处理？What happens to snake_case keys?

会转成 Kotlin 惯用的驼峰命名（user_name → userName），并用所选库的注解保留原始 JSON 键名，序列化和反序列化都能对上。They become idiomatic camelCase (user_name → userName) and the chosen library's annotation keeps the original JSON key, so (de)serialization still matches.

什么时候字段会变成可空类型？When does a field become nullable?

字段值为 null，或在数组里的某些对象中缺失时，会生成「类型? = null」；超过 Int 范围的整数会用 Long。When a value is null or the key is missing from some objects in an array, the field becomes "Type? = null"; integers beyond the Int range use Long.

「JSON 转 Kotlin 数据类」免费吗？数据会上传吗？Is the JSON to Kotlin Data Class free? Is my data uploaded?

「JSON 转 Kotlin 数据类」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 Kotlin Data Class 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.