HarmonyOS ArkTS调用index.d.ts里面的C接口有一个方法中的参数类型是Uint8Array，C侧改如何接收

示例参考如下：

// ArkTS传递Uint8Array参数 
import testNapi from 'libentry.so';

@Entry
@Component
struct Index {
  @State message: string = 'Hello World';

  build() {
    Row() {
      Column() {
        Text(this.message)
          .fontSize(50)
          .fontWeight(FontWeight.Bold)
          .onClick(() => {
            let temp = new Uint8Array(2);
            temp[0] = 1;
            temp[1] = 2;
            console.info(`Pure inputBuffer length: ${temp.length}`);
            let res = testNapi.uintArr(temp);
            console.info(`Pure outputBuffer: ${res}`);
          })
      }
      .width('100%')
    }
    .height('100%')
  }
}

Native侧可以使用napi_get_typedarray_info方法获取Uint8Array的详细信息。

// Native侧获取Uint8Array参数并返回到ArkTS侧
napi_value UintArr(napi_env env, napi_callback_info info) {
    size_t requireArgc = 1;
    size_t argc = 1;
    napi_value args[1] = {nullptr};

    napi_get_cb_info(env, info, &argc, args, nullptr, nullptr);

    napi_value inputArray = args[0];

    // 获取ArrayBuffer类型
    napi_typedarray_type type;
    napi_value inArrayBuffer;
    size_t byteOffset;
    size_t length;
    napi_get_typedarray_info(env, inputArray, &type, &length, nullptr, &inArrayBuffer, &byteOffset);
    if (type != napi_uint8_array) {
        return nullptr;
    }
    // 获取ArrayBuffer信息
    void *data = nullptr;
    size_t byte_length;
    napi_get_arraybuffer_info(env, inArrayBuffer, &data, &byte_length);

    // 构造ArrayBuffer并赋值
    napi_value output_buffer;
    void *output_ptr = nullptr;
    napi_create_arraybuffer(env, byte_length, &output_ptr, &output_buffer);
    napi_value outputArray;
    napi_create_typedarray(env, type, length, output_buffer, byteOffset, &outputArray);
    uint8_t *input_bytes = (uint8_t *)(data) + byteOffset;
    uint8_t *array = (uint8_t *)(output_ptr);
    for (size_t idx = 0; idx < length; idx++) {
        array[idx] = 3;
    }
    return outputArray;
}

// Native侧获取Uint8Array参数并返回到ArkTS侧
napi_value UintArr(napi_env env, napi_callback_info info) {
    size_t requireArgc = 1;
    size_t argc = 1;
    napi_value args[1] = {nullptr};

    napi_get_cb_info(env, info, &argc, args, nullptr, nullptr);

    napi_value inputArray = args[0];

    // 获取ArrayBuffer类型
    napi_typedarray_type type;
    napi_value inArrayBuffer;
    size_t byteOffset;
    size_t length;
    napi_get_typedarray_info(env, inputArray, &type, &length, nullptr, &inArrayBuffer, &byteOffset);
    if (type != napi_uint8_array) {
        return nullptr;
    }
    // 获取ArrayBuffer信息
    void *data = nullptr;
    size_t byte_length;
    napi_get_arraybuffer_info(env, inArrayBuffer, &data, &byte_length);

    // 构造ArrayBuffer并赋值
    napi_value output_buffer;
    void *output_ptr = nullptr;
    napi_create_arraybuffer(env, byte_length, &output_ptr, &output_buffer);
    napi_value outputArray;
    napi_create_typedarray(env, type, length, output_buffer, byteOffset, &outputArray);
    uint8_t *input_bytes = (uint8_t *)(data) + byteOffset;
    uint8_t *array = (uint8_t *)(output_ptr);
    for (size_t idx = 0; idx < length; idx++) {
        array[idx] = 3;
    }
    return outputArray;
}

index.d.ts声明接口。

export const uintArr: (a: Uint8Array) => object;