Book Image

Blazor WebAssembly by Example

By : Toi B. Wright
Book Image

Blazor WebAssembly by Example

By: Toi B. Wright

Overview of this book

Blazor WebAssembly makes it possible to run C# code on the browser instead of having to use JavaScript, and does not rely on plugins or add-ons. The only technical requirement for using Blazor WebAssembly is a browser that supports WebAssembly, which, as of today, all modern browsers do. Blazor WebAssembly by Example is a project-based guide for learning how to build single-page web applications using the Blazor WebAssembly framework. This book emphasizes the practical over the theoretical by providing detailed step-by-step instructions for each project. You'll start by building simple standalone web applications and progress to developing more advanced hosted web applications with SQL Server backends. Each project covers a different aspect of the Blazor WebAssembly ecosystem, such as Razor components, JavaScript interop, event handling, application state, and dependency injection. The book is designed in such a way that you can complete the projects in any order. By the end of this book, you will have experience building a wide variety of single-page web applications with .NET, Blazor WebAssembly, and C#.
Table of Contents (11 chapters)

Event handling

Razor components handle events by using an HTML element attribute named @on{EVENT} where EVENT is the name of the event.

The following code calls the OnClickHandler method when the button is clicked:

<button class="btn btn-success" @onclick="OnClickHandler">
    Click Me
</button>
@code {
    private void OnClickHandler()
    {
        // ...
    }
}

Since event handlers automatically trigger a UI render, we do not need to call StateHasChanged when processing them. Event handlers can be used to call both synchronous and asynchronous methods. Also, they can reference any arguments that are associated with the event.

The following code asynchronously calls the OnChangeHandler method when the checkbox is changed:

<input type="checkbox" @onchange="OnChangedHandler" />
@code {
 ...