Some test text!


Open a document

There are a few ways to open a document such as from a URL, a blob, the filesystem, or base64 data. Additionally, there are loading options to help WebViewer determine the type of the file being loaded.

Opening a document in WebViewer from base64 data

If you have the file data as a base64 string, the best way to load the document in WebViewer is to first convert it to a Blob and then load it as described for Blobs . Below is some example code showing how to convert base64 to a Blob.

function base64ToBlob(base64) {
  const binaryString = window.atob(base64);
  const len = binaryString.length;
  const bytes = new Uint8Array(len);
  for (let i = 0; i < len; ++i) {
    bytes[i] = binaryString.charCodeAt(i);

  return new Blob([bytes], { type: 'application/pdf' });

  .then(instance => {
    // `myBase64String` is your base64 data which can come
    // from sources such as a server or the filesystem
    instance.UI.loadDocument(base64ToBlob(myBase64String), { filename: 'myfile.pdf' });

    const { documentViewer } = instance.Core;
    documentViewer.addEventListener('documentLoaded', () => {
      // perform document operations

See more WebViewer events such as documentLoaded to understand when to execute API operations.

If you run into any issues loading a document, please visit our FAQ.

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