Introduction to .NET Blazor: A Quick Guide

C# 2/7/2024

Welcome to the exciting world of .NET Blazor! Whether you're a seasoned developer or new to the .NET ecosystem, Blazor offers a compelling approach to building interactive web applications using C#. This quick guide will introduce you to .NET, .NET Core, and Blazor, culminating in a step-by-step walkthrough to create your first "HelloWorld" Blazor application.

Understanding .NET and .NET Core

.NET is a free, open-source development platform maintained by Microsoft and the community. It's used for many types of applications, offering a unified framework for building web, desktop, mobile, gaming, and IoT applications. .NET supports multiple languages, but C# is one of the most popular for .NET development, thanks to its versatility and object-oriented features.
.NET Core, now just referred to as .NET from version 5.0 onwards, was initially created to modernize the platform, offering cross-platform support and improved performance. It represents a significant evolution, unifying the .NET ecosystem to provide a single, optimized runtime and framework for all .NET applications. This consolidation simplifies the development process and extends .NET's capabilities across all platforms and devices.

Blazor: The New Kid on the Block

Blazor is a framework within the .NET ecosystem for building interactive client-side web UI with .NET. Before Blazor, using .NET in web development typically meant server-side coding, with client-side logic handled separately in JavaScript. Blazor changes the game by allowing developers to use C# and .NET to run code directly in the browser using WebAssembly, as well as supporting server-side processing.

Why Blazor?

Unified Language Use: Developers can use C# across client-side and server-side, reducing the need to switch between languages for different parts of an application.
Modern Web Development Features: Blazor supports modern web development features, including components, routing, dependency injection, and more, all within the .NET ecosystem.
Leverage Existing .NET Libraries: With Blazor, the vast array of .NET libraries and tools are at your disposal for both client and server code, making it easier to share code and libraries.

Building Your First HelloWorld Blazor Application

Let's dive into creating a simple "HelloWorld" application using Blazor. This example will help you set up your development environment and give you a taste of Blazor's capabilities.

Prerequisites

.NET SDK (version 8.0 or later): Download and install from the .NET website.
A code editor: Visual Studio Code is recommended, with the C# extension installed.

Step 1: Create a New Blazor App

Open your terminal or command prompt and run the following command to create a new Blazor App project:
dotnet new blazor -o HelloWorldBlazor
This command creates a new directory named `HelloWorldBlazor` with a Blazor App project.

Step 2: Navigate to Your Project Directory

Change into the newly created project directory:

cd HelloWorldBlazor

Step 3: Run Your Application

Execute the following command to run your application:

dotnet run

This command compiles and launches your Blazor application. Once it's running, open your web browser and navigate to https://localhost:5001 to view your Blazor app.

Step 4: Customize the HelloWorld Component

Open the Pages folder in your project, and find the Index.razor file. This file contains the default page for your Blazor app. Replace the content with the following to create a simple HelloWorld message:

@page "/" <h1>Hello, World!</h1> Welcome to your new Blazor application.

Save the file and refresh your browser to see the changes.

Congratulations! You've just created your first Blazor application. This HelloWorld example is just the beginning. Blazor offers a rich set of features for building complex, interactive web applications with .NET.

Moving Forward

Now that you've dipped your toes into Blazor, consider exploring more about componentization, routing, and how to call web APIs from your Blazor apps. The .NET documentation provides extensive guides and tutorials to help you on your journey. Happy coding!