Show or hide the PDF Viewer dynamically in Blazor PDF Viewer Component

17 Dec 20222 minutes to read

In the below code, the PDF Viewer is hidden at page load. Then, on clicking a button, the PDFViewer container will be loaded. When the user clicks on a PDF file (here it is demonstrated with buttons), the PDF Viewer already present on the same page will be updated to show the selected document.

@using Syncfusion.Blazor.Buttons
@using Syncfusion.Blazor.PdfViewerServer;
@using Syncfusion.Blazor.PdfViewer;
@using System.Net;

    .e-spinner-pane {
        display: none !important;

<!--Show or hide the visibility of the PDF Viewer-->
<SfButton OnClick="ShowHidePdfViewer">@Label PDF Viewer</SfButton>

@if (IsShowPDFViewer)
    <SfButton OnClick="LoadDocument1">Physical Path</SfButton>    
    <SfButton OnClick="LoadDocument2">Remote Path</SfButton>    

    <div class="mt-2">
        <SfPdfViewerServer @ref="PdfViewerServerRef"

    SfPdfViewerServer PdfViewerServerRef { get; set; }

    string Base64Content { get; set; }

    bool IsShowPDFViewer { get; set; }

    string Label => IsShowPDFViewer ? "Hide" : "Show";

    //This method handles the visibility of the PDFViewer.
    void ShowHidePdfViewer() => IsShowPDFViewer = !IsShowPDFViewer;

    public void LoadDocument1()
        //Updates the PDF Viewer container width and height from externally.
        //Returns a byte array containing the contents of the file.
        byte[] byteArray = System.IO.File.ReadAllBytes("wwwroot/data/PDF Succinctly.pdf");
        //Sets the document path from base64 string.
        Base64Content = $"data:application/pdf;base64,{Convert.ToBase64String(byteArray)}";

    public async Task LoadDocument2()
        using (var webClient = new WebClient())
            //Downloads the resource as a byte array from the url specified. 
            var data = await webClient.DownloadDataTaskAsync("");
            //Sets the document path from base64 string.
            Base64Content = $"data:application/pdf;base64,{Convert.ToBase64String(data)}";



View sample in GitHub.