CLI Guide for .NET Core Applications: Building, Running, and Deploying

Introduction

Master the.NET Command Line Interface: A comprehensive guide to building, running, and deploying.NET Core applications using CLI tools for simplified development and efficient deployment.

The command-line interface (CLI) is a powerful tool for developers that enables efficient management of the entire lifecycle of a.NET Core application, from creation to deployment. This guide will provide a complete walkthrough of using the.NET CLI to build, run, and deploy.NET Core applications, making it an essential resource for developers who prefer command-line tools command over integrated development environments (IDEs).

Introduction to the.NET command-line interface

Before diving into the.NET CLI, make sure you have the.NET Core SDK installed on your system. The SDK includes the.NET command-line interface, which is required to build, compile, run, and deploy.NET Core applications. To verify your installation, open the command line or terminal and run:

dotnet --version

This command should return the version of the.NET Core SDK installed on your computer.

Creating a new.NET Core application

Start by creating a new.NET Core application. The.NET CLI supports various types of applications, including console apps, web apps, and more. To create a new console application, use the following command:

dotnet new console -n MyFirstDotNetApp

This command creates a new directory called MyFirstDotNetApp with a simple "Hello World" console application.

Build the application

Navigate to the application directory and create the application using the.NET CLI:

cd MyFirstDotNetApp

dotnet build

This command compiles the application and checks for compile-time errors, ensuring that the code is ready to run.

Running the application

To run the application, use the following command:

dotnet run

This command runs the application and you should see the output, typically "Hello World", in the console.

Understanding the structure of the.NET Core application

A.NET Core application is made up of several files, but two main files are worth noting:

• Program.cs - This file contains the entry point of the application, where execution begins.
• .csproj file - This is the project file for your application. Includes information such as SDK version, dependencies, and other configurations.

Adding dependencies

To add a package or dependency to your application, use the dotnet add package command followed by the package name. For example, to add Newtonsoft.Json, you would use:

dotnet add package Newtonsoft.Json

This command modifies the.csproj file to include the newly added package as a dependency.

Application deployment

Deployment often involves publishing the application to a directory with all the files needed to run the application. To publish a.NET Core application, use:

dotnet publish -c Release

This command compiles the application in release mode (optimized for performance) and places the output in the bin/Release directory or a subdirectory depending on the target framework. You can then deploy this output to your hosting environment.

To set a custom distribution directory use -o with the new directory path: for example:

dotnet publish -c Release -o /var/apps/helloworld

Deployment Considerations

• Environment Variables - Ensure that all environment-specific variables are set correctly in your deployment environment.
• Configuration files - Examine appsettings.json or other configuration files for environment-specific settings.
• Dependencies: Make sure all dependencies are resolved and properly packaged during the publish phase.

Conclusion

The.NET CLI is a versatile and efficient tool for managing.NET Core applications. By mastering CLI commands, developers can effectively manage the processes of creating, developing, and deploying their applications. This guide covers the basics to get you started, but the.NET CLI offers so much more. Explore the official.NET documentation to delve deeper into the capabilities of the.NET CLI and unlock its full potential in your development workflow.