Book Image

Blazor WebAssembly by Example, 2e - Second Edition

By : Toi B. Wright
5 (1)
Book Image

Blazor WebAssembly by Example, 2e - Second Edition

5 (1)
By: Toi B. Wright

Overview of this book

Blazor WebAssembly helps developers build web applications without the need for JavaScript, plugins, or add-ons. With its continued growth in popularity, getting started with Blazor now can open doors to new career paths and exciting projects – and Blazor WebAssembly by Example will make your first steps easier. This is a project-based guide that will teach you how to build single-page web applications with Blazor, focusing heavily on the practical over the theoretical by providing detailed step-by-step instructions for each project. The author also includes a video for each project showing her following the step-by-step instructions, so readers can use them if they're unsure about any particular step. In this updated edition, you'll start by building simple standalone web applications and gradually progress to developing more advanced hosted web applications with SQL Server backends. Each project will cover a different aspect of the Blazor WebAssembly ecosystem, such as Razor components, JavaScript interop, security, event handling, debugging on the client, application state, and dependency injection. The book’s projects get more challenging as you progress, but you don’t have to complete them in order, which makes this book a valuable resource for beginners as well as those who just want to dip into specific topics. By the end of this book, you will have experience and lots of know-how on how to build a wide variety of single-page web applications with .NET, Blazor WebAssembly, and C#.
Table of Contents (15 chapters)
13
Other Books You May Enjoy
14
Index

Controlling the user interface using authorization

After a user is authenticated, authorization rules are used to control what the user can see and do. The Authorize attribute and the AuthorizeView component are used to control the user interface.

The Authorize attribute

The Authorize attribute is used to require that the user is authorized to view the page that is decorated with the attribute. It should only be used on routable components. The following component includes the Authorize attribute:

Secure.razor

@page "/secure"
@using Microsoft.AspNetCore.Authorization
@attribute [Authorize]
<h2>Secure Page</h2>
Congratulations, you have been authenticated!

When an unauthenticated user tries to navigate to a page with the Authorize attribute, they are automatically redirected to the /authentication/login page.

TIP

You can require authentication for every page by adding the Authorize attribute to the _Imports.razor file. However...