WebAssembly application in Blazor PDF Viewer Component

17 Jan 20225 minutes to read

Note: There is a separate PDF Viewer component for Blazor server-side and Blazor WebAssembly applications.

  • The SfPdfViewerServer control is for Blazor server-side application. This control resides with Syncfusion.Blazor.PdfViewerServer.Windows NuGet package. This server-side control is highly recommended.
  • The SfPdfViewer control is for Blazor WebAssembly application. This control requires server-side processing to render the PDF files through web service. It resides with Syncfusion.Blazor.PdfViewer NuGet package.

This section briefly explains how to include a PDF Viewer in your Blazor WebAssembly application.

Step 1: Choose Create a new project from the Visual Studio dashboard. Click Next.

Creating New Project in Blazor

Step 2: Select Blazor WebAssembly App from the template, and then click Next button.

Blazor Application Template

Step 3: Now, the project configuration window will popup. Click Next button to modify the additional information.

Blazor Project Configuration

Step 4: Select the target Framework .NET 5.0 at the top of the application based on your required target and then click Create button to create a new Blazor WebAssembly application.

Blazor Server Application with Additional Information

Step 5: Installing Syncfusion Blazor packages in the application.

You can use any one of the below standard to install the Syncfusion Blazor library in your application.

  • Using Syncfusion Blazor individual NuGet Packages [New standard]

Starting with Volume 4, 2020 (v18.4.0.30) release, Syncfusion provides individual NuGet packages for our Syncfusion Blazor components. This new standard is highly recommended for your Blazor production applications. Refer to this section to know the benefits of the individual NuGet packages.

  1. Install Syncfusion.Blazor.PdfViewer NuGet package to the new application using the NuGet Package Manager. For more details about available NuGet packages, refer to the Individual NuGet Packages documentation.

  2. Right-click the project, and then select Manage NuGet Packages.

    Blazor NuGet Explorer

  3. Search Syncfusion.Blazor.PdfViewer keyword in the Browse tab and install Syncfusion.Blazor.PdfViewer NuGet package in the application.

    Searching Blazor PDFViewer NuGet Package

  4. The Syncfusion Blazor PdfViewer package will be included in the newly created project once the installation process is completed.

  • Using Syncfusion.Blazor NuGet Package [Old standard]


If you prefer the above new standard (individual NuGet packages), then skip this section. Using both old and new standards in the same application will throw ambiguous compilation errors.

  1. Now, install Syncfusion.Blazor NuGet package to the newly created application by using the NuGet Package Manager. Right-click the project and then select Manage NuGet Packages.

    Blazor NuGet Explorer

  2. Search Syncfusion.Blazor keyword in the Browse tab and install Syncfusion.Blazor NuGet package in the application.

    Searching Blazor NuGet Package

  3. The Syncfusion Blazor package will be installed in the project once the installation process is completed.

Step 6: Open ~/_Imports.razor file and import the Syncfusion.Blazor.PdfViewer when new standard is followed or import the Syncfusion.Blazor namespace when old standard is followed.

@using Syncfusion.Blazor.PdfViewer


@using Syncfusion.Blazor

Step 7: Add the Syncfusion bootstrap4 theme in the <head> element of the ~/wwwroot/index.html page.

When Syncfusion.Blazor.PdfViewer is used, use the following code.

        <link href="_content/Syncfusion.Blazor.Themes/bootstrap4.css" rel="stylesheet" />

When Syncfusion.Blazor is used, use the following code.

        <link href="_content/Syncfusion.Blazor/styles/bootstrap4.css" rel="stylesheet" />

Note: The same theme file can be referred through the CDN version by using https://cdn.syncfusion.com/blazor/19.4.38/styles/bootstrap4.css.

For Internet Explorer 11 kindly refer the polyfills. Refer the documentation for more information.

    <link href="https://cdn.syncfusion.com/blazor/19.4.38/styles/bootstrap4.css" rel="stylesheet" />
    <script src="https://github.com/Daddoon/Blazor.Polyfill/releases/download/3.0.1/blazor.polyfill.min.js"></script>

Step 8: Open the ~/Program.cs file and register the Syncfusion Blazor Service.

using Syncfusion.Blazor;

namespace BlazorWebAssembly
    public class Program
        public static async Task Main(string[] args)
            await builder.Build().RunAsync();

The dynamic script loading can be disabled and refer to the scripts from the application end by using the IgnoreScriptIsolation parameter in AddSyncfusionBlazor() at the program.cs. For more details, please refer here for how to refer custom/CDN resources.

Step 9: Now, add the PDF Viewer (WebAssembly) component to the ~/Pages/Index.razor page.

@using Syncfusion.Blazor.PdfViewer

<SfPdfViewer DocumentPath="PDF_Succinctly.pdf" ServiceUrl="https://ej2services.syncfusion.com/production/web-services/api/pdfviewer" Height="500px" Width="1060px"></SfPdfViewer>

Since Syncfusion PDF Viewer (Blazor WebAssembly) control depends on server-side processing to render the PDF files, it is mandatory to create a web service as mentioned here

Step 10: Run the application, the PDF Viewer component will be rendered in the web browser as shown in the following screenshot.

Blazor PDFViewer

Download the WebAssembly application from here.

You can refer to the Blazor PDF Viewer feature tour page for its groundbreaking feature representations. You can also explore the Blazor PDF Viewer example to understand how to explain core features of PDF Viewer.