> For the complete documentation index, see [llms.txt](https://developers-apps-in-toss.toss.im/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://developers-apps-in-toss.toss.im/documentation/api-and-sdk-zh/common/file-storage/file.md).

# 文件保存

### 保存文件

**SDK 函数：** `saveBase64Data`

`saveBase64Data` 该函数会将以字符串编码的 Base64 数据，使用指定的文件名和 MIME 类型保存到用户设备上。可以保存图片、文本、PDF 等多种格式的数据。

**签名**

```typescript
function saveBase64Data(params: SaveBase64DataParams): Promise<void>;
```

**参数**

* **params** · 必需 · `SaveBase64DataParams`

  这是一个包含要保存的数据和文件信息的对象。

  * **params.data** · 必需 · `string`

    这是以 Base64 格式编码的数据字符串。
  * **params.fileName** · 必需 · `string`

    这是要保存的文件名。还需要同时附上扩展名。例如，可以保存为 'example.png'。
  * **params.mimeType** · 必需 · `string`

    这是要保存的文件的 MIME 类型。例如，指定为 'image/png' 时是图片，'application/pdf' 是 PDF 文件。更多详情请参见 [MIME 文档](https://developer.mozilla.org/ko/docs/Web/HTTP/Guides/MIME_types)请参考。

**示例**

**将 Base64 图片数据保存到用户设备**

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

```js
import { saveBase64Data } from '@apps-in-toss/web-framework';

async function handleSaveBase64Data() {
  try {
    await saveBase64Data({
      data: 'iVBORw0KGgo...',
      fileName: 'some-photo.png',
      mimeType: 'image/png',
    });
    console.log('数据保存成功');
  } catch (error) {
    console.error('数据保存失败：', error);
  }
}
```

{% endtab %}

{% tab title="React" %}

```tsx
import { saveBase64Data } from '@apps-in-toss/web-framework';
import { Button } from '@toss/tds-mobile';

function SaveButton() {
  const handleSave = async () => {
    try {
      await saveBase64Data({
        data: 'iVBORw0KGgo...',
        fileName: 'some-photo.png',
        mimeType: 'image/png',
      });
    } catch (error) {
      console.error('数据保存失败：', error);
    }
  };

  return <Button onClick={handleSave}>保存</Button>;
}
```

{% endtab %}

{% tab title="React Native" %}

```tsx
import { saveBase64Data } from '@apps-in-toss/framework';
import { Button } from '@toss/tds-react-native';

function SaveButton() {
  const handleSave = async () => {
    try {
      await saveBase64Data({
        data: 'iVBORw0KGgo...',
        fileName: 'some-photo.png',
        mimeType: 'image/png',
      });
    } catch (error) {
      console.error('数据保存失败：', error);
    }
  };

  return <Button onPress={handleSave}>保存</Button>;
}
```

{% endtab %}
{% endtabs %}


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