> 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/thumbnail-controls.md).

# Thumbnail controls

Manipulate PDF with WebViewer thumbnail controls. You can rotate, add, move, delete, merge, and export PDF pages directly in the browser.

{% hint style="info" %}
**Requirements**

*These packages are required to use these features in production. Trial keys have unlimited access to all features*

<a href="/web/get-started/readme.md" class="button primary">Web SDK</a><a href="https://apryse.com/capabilities#PageManipulation" class="button primary">Package: Page Manipulation</a>
{% endhint %}

Sample JavaScript code to use thumbnail controls to perform page manipulation in the browser (no servers or other external dependencies required). This sample lets you rotate a PDF page and delete, move, or insert a new page into your document. There are two instances of WebViewer, so you can move pages between them. In the case of MS Office files (DOCX, XLSX, PPTX), documents are converted to PDF files where modifications are saved. This sample works on all browsers (including IE11) and mobile devices without using plug-ins.

For an example view our [Thumbnail Controls demo](https://sdk.apryse.com/samples/web/samples/pdf-manipulation/thumbnail-controls/).

Learn more about our [Web SDK](/web/get-started/guides.md).

{% tabs %}
{% tab title="JavaScript" %}
{% code lineNumbers="true" %}

```js
const viewers = [
  {
    initialDoc: 'https://pdftron.s3.amazonaws.com/downloads/pl/demo-annotated.pdf',
    domElement: 'leftPanel',
  },
  {
    initialDoc: 'https://pdftron.s3.amazonaws.com/downloads/pl/report.docx',
    domElement: 'rightPanel',
  },
];
let workerTransportPromise;

Core.setWorkerPath('../../../lib/core');
Core.getDefaultBackendType().then(pdfType => {
  workerTransportPromise = Core.initPDFWorkerTransports(pdfType, {});

  initializeWebViewer(viewers[0]);
  initializeWebViewer(viewers[1]);
});
// eslint-disable-next-line no-undef
const WebViewerConstructor = isWebComponent() ? WebViewer.WebComponent : WebViewer;

const initializeWebViewer = viewer => {
  WebViewerConstructor(
    {
      path: '../../../lib',
      // since there are two instance of WebViewer, use "workerTransportPromise" so viewers can share resources
      workerTransportPromise: {
        pdf: workerTransportPromise,
      },

      // set "useDownloader" to false to the either file is loaded
      useDownloader: false,

      // can load a office documents as PDFDocument by setting "loadAsPDF"
      loadAsPDF: true,

      initialDoc: viewer.initialDoc,
    },
    document.getElementById(`${viewer.domElement}`)
  ).then(instance => {
    const { documentViewer } = instance.Core;
    const { enableFeatures, enableElements, openElements, ThumbnailsPanel, loadDocument } = instance.UI;
    enableFeatures(['ThumbnailMultiselect', 'MultipleViewerMerging']);
    enableElements(['documentControl']);

    documentViewer.addEventListener('documentLoaded', () => {
      openElements(['thumbnailsPanel']);

      // select some pages
      ThumbnailsPanel.selectPages([1]);
    });

    document.getElementById(`${viewer.domElement}`).addEventListener('documentMerged', data => {
      // can use "documentMerged" event to track what is being merged into a document
      console.log(`From: ${data.detail.filename} pages: ${data.detail.pages}`);
    });

    // set up controls on the left side bar
    document.getElementById(`${viewer.domElement}-select`).onchange = e => {
      loadDocument(e.target.value);
    };

    document.getElementById(`${viewer.domElement}-file-picker`).onchange = e => {
      const file = e.target.files[0];

      if (file) {
        loadDocument(file);
      }
    };

    document.getElementById(`${viewer.domElement}-url-form`).onsubmit = e => {
      e.preventDefault();
      loadDocument(document.getElementById(`${viewer.domElement}-url`).value);
    };
  });
};
```

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


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