Setting Up Your Development Environment

Vaibhav • September 11, 2025

Before we can write our first line of C# code, we need to prepare the tools that will help us do it. In this article, we’ll walk through setting up a modern C# development environment from scratch. You’ll install the necessary software, write your first program, and understand how C# projects are structured behind the scenes.

Installing the .NET SDK

The .NET SDK (Software Development Kit) is the foundation of C# development. It includes the compiler, runtime, and command-line tools needed to build and run C# applications.

To install it:

  • Visit dotnet.microsoft.com/Download the .NET SDK (not just the runtime)
  • Download and run the installer for your operating system (Windows, macOS, or Linux)

After installation, open a terminal or command prompt and run: 

dotnet --version

If you see a version number, the SDK is installed correctly. This command confirms that the .NET CLI (Command Line Interface) is available and ready to use.

The .NET CLI is a powerful tool that lets you create, build, and run C# projects directly from the terminal-no IDE required.

Choosing an Editor: Visual Studio or VS Code

You can write C# code in any text editor, but using a modern IDE (Integrated Development Environment) makes life much easier. Microsoft offers two excellent options:

Visual Studio

This is the full-featured IDE for Windows. It includes a graphical interface, debugger, project templates, and more. Choose the “Community” edition-it’s free for individual developers and small teams.

Visual Studio Code (VS Code)

A lightweight, cross-platform editor that works on Windows, macOS, and Linux. It’s fast, customizable, and supports C# through the C# extension (powered by OmniSharp).

To set up VS Code for C#:

  • Install VS Code from code.visualstudio.com
  • Search for “C#” and install the official extension by Microsoft

If you're just starting out, VS Code is a great choice. It's simple, fast, and works well with the .NET CLI.

Creating Your First C# Project

Let’s create a simple console application that prints a message to the screen. Open your terminal and run: 

dotnet new console -n HelloWorld

This command does three things:

  • dotnet new console creates a new console application
  • -n HelloWorld names the project “HelloWorld”
  • It generates a folder with starter files

Navigate into the project folder: 

cd HelloWorld

Now run the program: 

dotnet run

You should see: 

Hello, World!

Congratulations! You’ve just written and executed your first C# program.

The dotnet run command compiles your code and then executes the resulting program in one step.

Understanding the Project Structure

Let’s take a closer look at what was created inside the HelloWorld folder:

  • Program.cs - This is the main source file. It contains the Main method, which is the entry point of your program.
  • HelloWorld.csproj - This is the project file. It defines the project type, target framework, and dependencies.
  • obj/ and bin/ - These folders are created when you build the project. They contain intermediate and compiled files.

Here’s what the default Program.cs looks like: 

using System;

class Program
{
    static void Main(string[] args)
    {
        Console.WriteLine("Hello, World!");
    }
}

Let’s break it down:

  • using System; brings in the System namespace, which includes the Console class.
  • class Program defines a class named Program. Every C# program must have at least one class.
  • static void Main(string[] args) is the entry point. It’s where the program starts running.
  • Console.WriteLine(...) prints text to the screen.

Always start with a clean folder for each new project. This keeps your code organized and avoids conflicts.

Compiling Without Running

Sometimes you want to compile the code without running it. Use: 

dotnet build

This creates an executable in the bin/Debug/netX.X/ folder (where X.X is your .NET version). You can run it directly: 

dotnet bin/Debug/net8.0/HelloWorld.dll

This separation is useful when you want to build once and run multiple times-especially in larger projects.

Working with VS Code

If you’re using VS Code, open the project folder: 

code .

VS Code will detect the C# project and prompt you to install required assets. Accept the prompt. You’ll now have:

  • Syntax highlighting
  • Code completion
  • Integrated terminal
  • Debugging support

You can run the program using the terminal or by pressing F5 to start debugging.

The first time you run or debug, VS Code creates a .vscode folder with configuration files. These help it understand how to build and run your project.

Common Setup Issues

If something doesn’t work, here are a few things to check:

  • Make sure the .NET SDK is installed and dotnet --version works
  • Ensure you’re in the correct folder (where the .csproj file is)
  • Restart VS Code after installing the C# extension
  • Use the terminal inside VS Code for consistent behavior

If you’re on Linux or macOS, you may need to install additional dependencies. The .NET install page provides platform-specific instructions.

Summary

In this article, you set up your C# development environment and wrote your first program. You learned how to:

  • Install the .NET SDK
  • Choose between Visual Studio and VS Code
  • Create and run a new C# project using the CLI
  • Understand the basic folder and file structure of a C# project
  • Use VS Code for editing, running, and debugging

With your environment ready, you’re now equipped to start exploring the language itself. In the next article, we’ll take a closer look at your first C# program and explain how it works line by line.