Introduction to ASP.NET Core: Building Web Apps


ASP.NET Core is a modern, cross-platform, and open-source framework for building web applications. It's the next generation of ASP.NET and is designed to be more modular, lightweight, and performant. In this guide, we'll introduce you to ASP.NET Core and show you how to start building web applications with it.


Before you dive into ASP.NET Core development, make sure you have the following prerequisites:

  • Visual Studio (Windows) or Visual Studio Code (cross-platform) installed on your computer. You can download Visual Studio Community for free.
  • The .NET Core SDK, which is required for building and running ASP.NET Core applications.
  • Basic knowledge of C# programming and web development concepts.

Key Features of ASP.NET Core

ASP.NET Core comes with several key features that make it a popular choice for web app development:

  • Cross-Platform: ASP.NET Core is designed to run on Windows, Linux, and macOS, giving developers the flexibility to choose their preferred development environment.
  • High Performance: It's optimized for high performance and can handle a large number of concurrent requests efficiently.
  • Modularity: ASP.NET Core is modular, allowing you to include only the components your application needs, reducing bloat and improving performance.
  • Integrated Dependency Injection: It provides a built-in dependency injection container for managing application services.
  • Cross-platform Development: You can develop ASP.NET Core applications on Windows, macOS, or Linux using a variety of editors and IDEs.

Sample ASP.NET Core Code

Below is a simple example of ASP.NET Core code for creating a basic web application that displays "Hello, ASP.NET Core!" in the browser.

ASP.NET Core Code (Startup.cs):

using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Hosting;
using Microsoft.AspNetCore.Http;
using Microsoft.Extensions.DependencyInjection;
public class Startup
public void ConfigureServices(IServiceCollection services)
public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
if (env.IsDevelopment())
app.Run(async (context) =>
await context.Response.WriteAsync("Hello, ASP.NET Core!");

Getting Started with ASP.NET Core

To start building web apps with ASP.NET Core, follow these steps:

  1. Create a new ASP.NET Core project in Visual Studio or Visual Studio Code.
  2. Understand the structure of an ASP.NET Core application, including middleware, services, and controllers.
  3. Configure routing to define how URLs map to controller actions.
  4. Create controllers and views to handle user requests and generate dynamic web content.
  5. Run your ASP.NET Core application and view it in a web browser.


ASP.NET Core is a versatile and powerful framework for building modern web applications. This guide provides an introduction to ASP.NET Core and the basics of creating web apps with it. As you delve deeper into ASP.NET Core development, you can explore advanced topics like authentication, data access, and API development to build feature-rich web applications.