napi_add_finalizer

napi_status napi_add_finalizer(napi_env env,
                               napi_value js_object,
                               void* native_object,
                               napi_finalize finalize_cb,
                               void* finalize_hint,
                               napi_ref* result); 拷贝

• [in] env：调用 API 的环境。

  ¥[in] env: The environment that the API is invoked under.

• [in] js_object：原生数据将附加到的 JavaScript 对象。

  ¥[in] js_object: The JavaScript object to which the native data will be attached.

• [in] native_object：将附加到 JavaScript 对象的原生数据。

  ¥[in] native_object: The native data that will be attached to the JavaScript object.

• [in] finalize_cb：当 JavaScript 对象准备好进行垃圾回收时，将用于释放原生数据的原生回调。napi_finalize 提供了更多详细信息。

  ¥[in] finalize_cb: Native callback that will be used to free the native data when the JavaScript object is ready for garbage-collection. napi_finalize provides more details.

• [in] finalize_hint：传递给完成回调的可选上下文提示。

  ¥[in] finalize_hint: Optional contextual hint that is passed to the finalize callback.

• [out] result：对 JavaScript 对象的可选引用。

  ¥[out] result: Optional reference to the JavaScript object.

如果 API 成功，则返回 napi_ok。

¥Returns napi_ok if the API succeeded.

添加 napi_finalize 回调，当 js_object 中的 JavaScript 对象准备好进行垃圾回收时将调用该回调。此 API 与 napi_wrap() 类似，不同之处在于：

¥Adds a napi_finalize callback which will be called when the JavaScript object in js_object is ready for garbage collection. This API is similar to napi_wrap() except that:

• 以后无法使用 napi_unwrap() 检索原生数据，

  ¥the native data cannot be retrieved later using napi_unwrap(),

• 以后也不能使用 napi_remove_wrap() 将其删除，并且

  ¥nor can it be removed later using napi_remove_wrap(), and

• 可以使用不同的数据项多次调用 API，以便将它们中的每一个附加到 JavaScript 对象，并且

  ¥the API can be called multiple times with different data items in order to attach each of them to the JavaScript object, and

• API 操作的对象可以与 napi_wrap() 一起使用。

  ¥the object manipulated by the API can be used with napi_wrap().

警告：可选的返回引用（如果获得）应仅通过 napi_delete_reference 删除以响应最终回调调用。如果在此之前删除它，则可能永远不会调用 finalize 回调。因此，在获取引用时，还需要一个 finalize 回调，以便能够正确处理引用。

¥Caution: The optional returned reference (if obtained) should be deleted via napi_delete_reference ONLY in response to the finalize callback invocation. If it is deleted before then, then the finalize callback may never be invoked. Therefore, when obtaining a reference a finalize callback is also required in order to enable correct disposal of the reference.