As we will be exploring fundamental concepts of Blazor and web development, you won’t need any paid add-ons or additional tools. You will, however, need the following:

• A modern IDE (of your choice)
• A modern web browser (supporting WebAssembly)
• A Blazor project

All the code examples (and data samples) that you’ll see next can be found in a dedicated GitHub repository at:

https://github.com/PacktPublishing/Blazor-Web-Development-Cookbook/tree/main/BlazorCookbook.App.Client/Chapters/Chapter02

In this recipe, we introduce the foundational concept of data binding in Blazor applications. This feature bridges the gap between the user interface and the application’s data or state. A deep understanding of this concept will allow you to level up the interactivity of your projects. We start with mastering the basics.

Let’s bind a simple text field to a backing variable to see the data flowing from the user interface to the backend.

Getting ready

Before you dive into binding, create a Recipe01 directory – this will be your working directory.

How to do it…

Follow these steps to bind a C# value with a markup element:

1. Add a routable IntroduceYourself component that renders in an InteractiveWebAssembly mode:

   @page "/ch02r01"
   @rendermode InteractiveWebAssembly

2. Inside the @code block of IntroduceYourself, initialize a User variable to store the user input value:

   @code {
      ...

Now, we will dive into targeted and efficient handling of user interactions in Blazor applications. While general data binding is crucial, binding specific actions to specific DOM events takes your application’s interactivity to the next level. This approach allows for a more controlled and responsive user experience. You can directly link an event, such as a click or a key press, to a corresponding C# method or action. You’ll learn how to identify and bind to these events and which events are bindable.

Let’s implement a simple text field but trigger binding as the user types, not when they exit the field, which is the default behavior.

Getting ready

Before exploring binding on a specific event, do the following:

• Create a Recipe02 directory – this will be your working directory
• Copy your IntroduceYourself component from the Binding values with markup elements recipe or copy its implementation from the...

Asynchronous actions are pivotal in modern web applications, especially when dealing with data-intensive operations such as fetching data from an API or database. It’s also crucial that your application remains responsive as it’s executing a long-running task. In this recipe, I’ll guide you through data binding when working with asynchronous tasks. You will learn how to integrate asynchronous actions, allowing non-blocking UI updates and smoother user experiences.

Let’s enable an auto-complete feature on a simple input field and generate a list of suggestions as the user types their name.

Getting ready

Before diving into the auto-complete implementation, do the following:

• Create a Recipe03 directory – this will be your working directory
• Copy your IntroduceYourself component from the Binding to a specific DOM event recipe or copy its implementation from the Chapter02/Recipe02 directory...

Data binding is not just about connecting a UI element to a data source. It’s also about how data is retrieved and updated. Customizing these get and set operations makes state management and data flow more flexible. In this recipe, I’ll guide you through the caveats of using get and set explicitly and executing asynchronous logic when setting values. These mechanisms will allow you to simplify your code and take even greater control of the interactivity of your Blazor application.

Let’s implement a simple text field with explicit get and set operations so we can execute additional, asynchronous logic as binding is commencing.

Getting ready

This time, we will take a shortcut with preparations for this upcoming recipe:

• Create a Recipe04 directory – this will be your working directory
• Copy your IntroduceYourself component from the Performing asynchronous actions after binding recipe or copy its implementation...

The bind-Value pattern is a game-changer in simplifying the linking process of your UI elements to data properties. It enhances the clarity and conciseness of your code by reducing the boilerplate often associated with handling two-way data binding. In this recipe, I will guide you through a practical example, showcasing the pattern’s utility in creating more maintainable and simple code, ultimately enhancing your development workflow.

Let’s implement a component that allows binding directly to its parameters in a structure similar to the standard binding to HTML elements.

Getting ready

Before we start implementing a component that enables the bind-Value pattern, do the following:

• Create a Recipe05 directory – this will be your working directory
• Next to Recipe05, copy the Chapter02/Data directory from the GitHub repository, containing SkillLevel and DataSeed, required in this recipe

How...

When building web applications that interact with external data sources, it’s common to trigger API calls in response to user input. However, this can lead to a flood of requests, straining the API and degrading the user’s experience. To address that challenge, we’ll implement input throttling – a technique that moderates the rate at which requests are sent based on user input. In this recipe, I will guide you through setting up input throttling in a Blazor component, ensuring efficient and responsible usage of external APIs. You’ll create more robust and user-friendly applications capable of handling a heavy load of user interactions without overwhelming your data providers.

Let’s implement a simple text field that uses throttling to limit calls to the external API and seamlessly waits for a user to finish typing.

Getting ready

Before you dive into throttling implementation, do the following...