> For the complete documentation index, see [llms.txt](https://documentation.pushly.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://documentation.pushly.com/pushly-ja/integration/implementation-steps/react-native/sdk-react-native/id-tong-qi.md).

# ID同期

## 購読者の外部IDを設定する

購読者に一意のユーザーIDを提供すると、後で API を通じてその購読者とやり取りできるようになります。

購読者の外部IDが設定されたら、当社チームと連携して双方向の自動データ同期を構築できます。以下のユースケースは、パブリッシャーがサーバー間リクエストを通じて外部IDを使用する一般的な方法です。

* 個々の購読者にプログラムで通知を送信する
* 購読解除リクエストを処理する
* 購読者のプロフィール属性とイベントを追加および削除する

{% tabs %}
{% tab title="React" %}

```tsx
PushSDK.UserProfile.setExternalId("external-id");
```

{% endtab %}
{% endtabs %}

購読者にすでに External ID がタグ付けされているかどうかも確認できます:

{% tabs %}
{% tab title="React" %}

```tsx
const currentExternalId = await PushSDK.UserProfile.getExternalId();
```

{% endtab %}
{% endtabs %}


---

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