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

Uploading files

The InputFile component is a built-in Blazor component that is used to upload files into a Blazor app. It renders an HTML input element of type file and supplies a stream for the contents of the file. It is in the Microsoft.AspNetCore.Components.Forms namespace.

The OnChange event of the InputFile component is used to set the callback that gets invoked when a file is selected. This is an example of an InputFile component that invokes the OnChangeHandler method when a file is selected:

<InputFile OnChange="OnChangeHandler" 
           accept="image/png, image/jpeg" />

This is the resulting HTML markup from the preceding example:

<input accept="image/png, image/jpeg" type="file" _bl_2="">

In the preceding HTML markup, the _bl_2 attribute is used for Blazor’s internal processing, but everything else is a typical input element. The accept attribute is used to filter the types of...