.NET Insights

Introduction

Cross-platform development is a crucial aspect of modern software engineering. It allows developers to write applications that can run on multiple operating systems, such as Windows, macOS, and Linux, without major modifications. .NET Core, developed by Microsoft, is a powerful cross-platform framework that enables developers to create versatile applications across different environments. This article delves into cross-platform development in .NET Core, its advantages, and practical examples.

Understanding .NET Core

.NET Core is an open-source, modular, and high-performance framework designed to run on multiple platforms. It is a successor to the .NET Framework, offering enhanced capabilities for modern development scenarios, including cloud applications, microservices, and cross-platform applications.

Key Features of .NET Core

• Cross-Platform Support: Applications can run on Windows, macOS, and Linux.
• Open Source: The entire .NET Core platform is available under an open-source license.
• Modular Architecture: Developers can use only the necessary libraries, making applications lightweight and efficient.
• High Performance: Optimized performance and reduced memory footprint.
• Container Support: Native support for Docker and Kubernetes.
• Microservices Compatibility: Ideal for building scalable and independent services.
• Comprehensive Tooling: Supports development using Visual Studio, Visual Studio Code, and command-line tools.

Setting Up a Cross-Platform .NET Core Application using Visual Studio

Step 1: Install Visual Studio

Download and install Visual Studio with the .NET Core development workload. Ensure that you select the required components, including ASP.NET Core and development tools for Windows, macOS, or Linux.

Step 2: Create a New .NET Core Application

1. Open Visual Studio.
2. Click on Create a new project.
3. Select Console App (.NET Core) and click Next.
4. Provide a project name, choose a location, and click Create.
5. Wait for the project to be initialized.
6. Open Program.cs and verify the Main method, which should contain:

using System;

class Program
{
    static void Main()
    {
        Console.WriteLine("Hello, Cross-Platform World!");
    }
}

Step 3: Run the Application

1. Click on Start (or press F5) to compile and execute the application.
2. The output should display: Hello, Cross-Platform World!.

Developing a Cross-Platform Web API in .NET Core

Let’s build a simple cross-platform Web API using Visual Studio.

Step 1: Create an ASP.NET Core Web API Project

1. Open Visual Studio.
2. Click on Create a new project.
3. Select ASP.NET Core Web API and click Next.
4. Provide a project name, choose a location, and click Create.
5. Select .NET Core and ASP.NET Core 6.0 (or latest version), then click Create.
6. Wait for Visual Studio to set up the project and restore dependencies.

Step 2: Define a Simple API Endpoint

1. In Solution Explorer, navigate to Controllers.
2. Right-click on Controllers and select Add > Controller.
3. Choose API Controller – Empty and name it HelloController.
4. Modify HelloController.cs as follows:

using Microsoft.AspNetCore.Mvc;

namespace CrossPlatformAPI.Controllers
{
    [ApiController]
    [Route("api/[controller]")]
    public class HelloController : ControllerBase
    {
        [HttpGet]
        public IActionResult Get()
        {
            return Ok("Hello, Cross-Platform World!");
        }
    }
}

Step 3: Run the API

1. Click on Start (or press F5) to build and run the application.
2. The API will be available at https://localhost:5001/api/hello.
3. Open a web browser or use Postman to send a GET request to https://localhost:5001/api/hello.
4. The response should display Hello, Cross-Platform World!.

Deploying a .NET Core Application Across Platforms

Running on Windows

1. Open Visual Studio and click Start.
2. The application will launch in a terminal window or a web browser.

Running on macOS and Linux

1. Install Visual Studio for Mac or Visual Studio Code.
2. Open the project and build the application.
3. Click Run or execute the application from the terminal using:

dotnet run

Using Docker for Cross-Platform Deployment

To containerize the application:

1. Add a Dockerfile to the project:

FROM mcr.microsoft.com/dotnet/aspnet:6.0 AS base
WORKDIR /app
COPY . .
ENTRYPOINT ["dotnet", "CrossPlatformAPI.dll"]

2. Right-click the project in Solution Explorer and select Add > Docker Support.
3. Click Start to build and run the container.
4. To manually build and run the Docker image, use:

docker build -t crossplatformapi .
docker run -p 5000:80 crossplatformapi

5. The API will be accessible at http://localhost:5000/api/hello.

Conclusion

.NET Core simplifies cross-platform development by providing a unified runtime, tools, and APIs for Windows, macOS, and Linux. With its powerful features and ease of deployment, it is an excellent choice for building high-performance, scalable applications. Whether developing a console application, web API, or cloud service, .NET Core ensures seamless execution across platforms. Using Visual Studio, developers can efficiently build, debug, and deploy applications with minimal effort, making it a preferred choice for cross-platform development.