.NET Core Getting Started Guide

What Is .NET Core

.NET Core is a cross-platform, open-source development framework for building modern web applications, microservices, mobile apps, and desktop applications.

Key Features

• Cross-platform: Supports Windows, Linux, and macOS
• High performance: Performance comparable to Node.js and Go
• Open source: Source code is hosted on GitHub
• Modular: Reference NuGet packages as needed

Setting Up the Development Environment

Installing the .NET SDK

# Windows
winget install Microsoft.DotNet.SDK.8

# macOS
brew install dotnet-sdk

# Linux (Ubuntu)
sudo apt-get update && sudo apt-get install -y dotnet-sdk-8.0

Creating Your First Project

# Create a console application
dotnet new console -n HelloWorld

# Enter the project directory
cd HelloWorld

# Run the project
dotnet run

Core Concepts

1. Dependency Injection

public void ConfigureServices(IServiceCollection services)
{
    services.AddScoped<IMyService, MyService>();
    services.AddSingleton<IMySingleton, MySingleton>();
    services.AddTransient<IMyTransient, MyTransient>();
}

2. Middleware

public void Configure(IApplicationBuilder app)
{
    app.UseRouting();
    app.UseAuthorization();
    app.UseEndpoints(endpoints =>
    {
        endpoints.MapControllers();
    });
}

3. Asynchronous Programming

public async Task<IActionResult> GetAsync()
{
    var data = await _service.FetchDataAsync();
    return Ok(data);
}

Summary

.NET Core is a powerful and flexible development framework suitable for building many types of applications. Mastering .NET Core is essential for modern backend development.

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Author: Lei Tao
Date: January 15, 2024