What is ASP.NET Core?

This page is carried over from the technology overview on our previous site. Version and tooling details reflect the time it was written.

ASP.NET Core is an open source web application framework developed by Microsoft. It has become a common choice for developing web applications using the C# programming language.

What is ASP.NET Core?

ASP.NET Core is an open source web application framework. Developed by Microsoft, this framework runs on the .NET Core runtime. ASP.NET Core is designed to ensure portability across different operating systems and platforms. Therefore, it has become a very popular choice for developing web applications.

What is ASP.NET Core MVC?

ASP.NET Core MVC is a web application framework based on the Model-View-Controller (MVC) design pattern. This pattern breaks an application into three separate components: model, view, and controller. The model manages the data layer of the application, the view manages the user interface, and the controller manages the interaction between the model and the view.

ASP.NET Core MVC runs on the .NET Core runtime and inspects requests from the browser, accesses data using the model, creates the view, and finally sends it as a response to the user.

What is ASP.NET Core Web API?

ASP.NET Core Web API is a web application framework used to create RESTful APIs. These APIs facilitate data sharing between different devices using the HTTP protocol.

ASP.NET Core Web API runs on the .NET Core runtime and processes requests using different HTTP methods. As a result of these requests, it returns responses in JSON or XML format.

Creating a Sample Web Application Using ASP.NET Core

Below is an example of a simple web application using ASP.NET Core. This example creates a welcome message using data from a form where a person enters their first and last name.

// HomeController.cs
using Microsoft.AspNetCore.Mvc;
public class HomeController : Controller
{
    [HttpGet]
    public IActionResult Index()
    {
        return View();
    }     [HttpPost]
    public IActionResult Index(string firstName, string lastName)
    {
        ViewData["Message"] = $"Welcome, {firstName} {lastName}!";
        return View();
    }
}

<!-- Index.cshtml -->
<h1>Welcome!</h1>
<form method="post">
    <label for="firstName">First Name:</label>
    <input type="text" id="firstName" name="firstName" required>
   <label for="lastName">Last Name:</label>
    <input type="text" id="lastName" name="lastName" required>   
   <button type="submit">Submit</button>
</form>