> For the complete documentation index, see [llms.txt](https://docs.apryse.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.apryse.com/web/get-started/samples/webviewer-cors.md).

# Implement WebViewer Cross-Origin Resource Sharing - CORS

Loading WebViewer's lib from a different domain using CORS.

This sample shows how to serve WebViewer's lib from a different domain. This project implements Cross-Origin Resource Sharing (CORS) as a client server `webviewer-app` that fetches resources from a server `webviewer-lib` in another domain. The dependency reference to `@pdftron/webviewer` exists in both `webviewer-lib\package.json` and `webviewer-app\package.json`.

It is recommended to serve the WebViewer lib on the same domain as the app itself for additional performance and security.

WebViewer provides a slick out-of-the-box responsive UI that enables you to view, annotate and manipulate PDFs and other document types inside any web project.

Click the button below to view the full project in GitHub.

{% tabs %}
{% tab title="TSX" %}
{% code title="App.tsx" lineNumbers="true" %}

```tsx
import React, { useEffect, useRef } from 'react';
import WebViewer from '@pdftron/webviewer';
import './App.css';

function App() {
  const viewer = useRef<HTMLDivElement>(null);

  useEffect(() => {
    WebViewer(
      {
        path: 'http://localhost:8081/lib/',
      },
      viewer.current as HTMLDivElement,
    ).then((instance) => {
      const url = 'https://pdftron.s3.amazonaws.com/downloads/pl/webviewer-demo.pdf';
      instance.UI.loadDocument(url);

      const { documentViewer, Annotations } = instance.Core;
      documentViewer.addEventListener('documentLoaded', () => {
        const annotManager = documentViewer.getAnnotationManager();
        const rectangle = new Annotations.RectangleAnnotation();
        rectangle.PageNumber = 2;
        rectangle.X = 100;
        rectangle.Y = 100;
        rectangle.Width = 250;
        rectangle.Height = 250;
        rectangle.Author = annotManager.getCurrentUser();
        annotManager.addAnnotation(rectangle);
      });
    });

  }, []);

  return (
    <div className="App">
      <div className="webviewer" ref={viewer}></div>
    </div>
  );
}

export default App;

```

{% endcode %}
{% endtab %}
{% endtabs %}

[View the full sample on GitHub](https://github.com/ApryseSDK/webviewer-samples/tree/main/webviewer-cors)


---

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