Get Base64 value from a loaded PDF in ASP.NET Core

Overview

This guide shows how to get the base64-encoded value of a PDF loaded in the Syncfusion ASP.NET Core PDF Viewer. Use this to send the PDF as a Base64 string or process it on the client.

How to retrieve Base64 value

Step 1: Follow the steps in the Syncfusion ASP.NET Core PDF Viewer getting started guide to create a simple viewer sample.

Step 2: Add a button to trigger the Base64 conversion.

<div class="text-center">
    <button id="getBase64">Get Base64</button>
    <ejs-pdfviewer id="pdfviewer" style="height:600px" resourceUrl="https://cdn.syncfusion.com/ej2/27.2.2/dist/ej2-pdfviewer-lib" documentPath="https://cdn.syncfusion.com/content/pdf/pdf-succinctly.pdf">
    </ejs-pdfviewer>
</div>

<script type="text/javascript">
    document.addEventListener('DOMContentLoaded', function () {
        var pdfViewer = document.getElementById('pdfviewer').ej2_instances[0];
        document.getElementById('getBase64').addEventListener('click', function () {
            base64ofloadedDocument();
        });
        function base64ofloadedDocument() {
            pdfViewer.saveAsBlob().then(function (value) {
                var data = value;
                var reader = new FileReader();
                reader.readAsDataURL(data);
                reader.onload = function () {
                    var base64data = reader.result;
                    console.log(base64data);
                };
            });
        }
    });
</script>

Conclusion

With these steps, a loaded PDF can be converted to a Base64 string on button click for transfer or additional processing.

View sample in GitHub