> 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-en/sdk/domains-api/file/file.openpdfviewer.md).

# File.openPDFViewer

> Functional API `openPDFViewer`You can use the same functionality with it as well.

### Feature description

Open Base64-encoded PDF data in the native PDF viewer. When the user closes the viewer `'CLOSE'`is returned.

Toss app Android/iOS `5.261.0` can be used on versions above. Before calling, `File.openPDFViewer.isSupported()`you can check support. If you call it on an unsupported version, `UNSUPPORTED_APP_VERSION` an error occurs.

### Type

```ts
File.openPDFViewer(params: OpenPDFViewerParams): Promise<OpenPDFViewerResult>;
```

**Params**

```ts
type OpenPDFViewerParams = {
  data: string;
  filename?: string;
};
```

**Response**

```ts
type OpenPDFViewerResult = "CLOSE";
```

### Error code

The error code is the `error.code` value.

| Code                      | Description                                                                                                                                                                                                                              |
| ------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `UNSUPPORTED_APP_VERSION` | If the running Toss app version does not support this feature, it occurs immediately upon calling. `File.openPDFViewer.isSupported()`Check in advance with, and if it occurs `error.message`show the user the (update guidance message). |
| `INVALID_REQUEST`         | This occurs when the request parameters are invalid.                                                                                                                                                                                     |
| `INVALID_DATA`            | This is when the PDF data is invalid.                                                                                                                                                                                                    |
| `PDF_VIEWER_ERROR`        | This is when an error occurs while opening the PDF viewer.                                                                                                                                                                               |

### Example code

```js
import { File } from "@apps-in-toss/web-framework";

async function handleOpenPdf() {
  if (!File.openPDFViewer.isSupported()) {
    console.log("The PDF viewer is not available in the current version of the Toss app.");
    return;
  }

  try {
    const result = await File.openPDFViewer({
      data: "JVBERi0xLjQK...",
      filename: "document.pdf",
    });

    if (result === "CLOSE") {
      console.log("The PDF viewer has been closed.");
    }
  } catch (error) {
    console.error("PDF viewer error:", error);
  }
}

document.querySelector("#open-pdf").addEventListener("click", handleOpenPdf);
```


---

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