ASP.NET Core is a powerful and flexible framework for building web applications and APIs. It provides developers with a rich set of tools and features for creating high-performance, scalable, and secure web applications. In this blog post, we’ll explore how to implement a minimal API in ASP.NET Core.

What is a Minimal API?

A Minimal API is a new way to create APIs in ASP.NET Core 6.0. It is designed to make API development simpler, faster, and more intuitive. With Minimal API, you can create an API with just a few lines of code. It provides a lightweight and simplified programming model that removes a lot of the boilerplate code that is typically required to create APIs.

Creating a Minimal API

To create a minimal API in ASP.NET Core, you’ll need to create a new ASP.NET Core project. You can do this by using the dotnet new command in the command line or by using the New Project dialog in Visual Studio.

Once you have created your project, you’ll need to add the necessary NuGet packages. You can do this by adding the following packages to your project:

dotnet add package Microsoft.AspNetCore.Mvc
dotnet add package Microsoft.AspNetCore.Http

Next, you’ll need to create a new class that will serve as the entry point for your API. This class should inherit from the Microsoft.AspNetCore.Builder.IEndpointRouteBuilder interface. Here’s an example:

using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Mvc;

var builder = WebApplication.CreateBuilder(args);

builder.Services.AddControllers();

var app = builder.Build();

app.UseRouting();

app.UseEndpoints(endpoints =>
{
    endpoints.MapGet("/", async context =>
    {
        await context.Response.WriteAsync("Hello, World!");
    });

    endpoints.MapControllers();
});

app.Run();

This code creates a new ASP.NET Core web application using the WebApplication.CreateBuilder method. It then adds the Microsoft.AspNetCore.Mvc and Microsoft.AspNetCore.Http NuGet packages to the project and creates a new IEndpointRouteBuilder instance.

The UseRouting method is used to configure the routing middleware, which is responsible for mapping incoming requests to their corresponding endpoints. The MapGet method is used to map a GET request to the root URL (“/”) to a lambda function that writes “Hello, World!” to the response stream.

The MapControllers method is used to map HTTP requests to controller actions. This is done by convention, where the route templates are generated based on the name of the controller and its action methods.

Finally, the Run method is used to run the web application. This starts the HTTP server and begins listening for incoming requests.

Conclusion

In this blog post, we’ve explored how to implement a minimal API in ASP.NET Core. We’ve seen how Minimal API can simplify the process of creating APIs by removing a lot of the boilerplate code that is typically required. With Minimal API, you can create an API with just a few lines of code, making it faster and easier to get started with API development in ASP.NET Core.