Build an ASP.NET Core app on a Mac or Linux using Visual Studio Code

This article will show you how to write your first ASP.NET Core application on macOS or Linux.

Setting up your development environment

Download and install .NET Core and Visual Studio Code with the C# extension.

Scaffolding applications using dotnet new

We will be using dotnet new to generate a new web application using the "Empty Web Template". Create a working directory for your project called firstapp . cd to firstapp.

Start Visual Studio Code and open the firstapp folder. Press Ctrl + '`' (the back-quote character) to open an embedded terminal in VS Code. Alternatively, use a separate terminal window. Run the dotnet new command to create a new web application, passing the mvc parameter as the template type.

dotnet new mvc

If you get an error running dotnet new mvc, install the latest .NET Core. When the CLI command completes; the following output and files are produced.

Content generation time: 79.6691 ms
The template "Empty ASP.NET Core Web Application" created successfully.
  • Startup.cs : Startup Class - class configures the request pipeline that handles all requests made to the application.
  • Program.cs : Program Class that contains the Main entry point of the application.
  • firstapp.csproj : Project file MSBuild Project file format for ASP.NET Core applications. Contains Project to Project references, NuGet References and other project related items.
  • appsettings.json / appsettings.Development.json : Environment base app settings configuration file. See Configuration.
  • bower.json : Bower package dependencies for the project.
  • .bowerrc : Bower configuration file which defines where to install the components when Bower downloads the assets.
  • bundleconfig.json : configuration files for bundling and minifying front-end JavaScript and CSS assets.
  • Views : Contains the Razor views. Views are the components that display the app's user interface (UI). Generally, this UI displays the model data.
  • Controllers : Contains MVC Controllers, initially HomeController.cs. Controllers are classes that handle browser requests.
  • wwwroot : Web application root folder.

For more information see The MVC pattern.

Developing ASP.NET Core applications on a Mac and Linux with Visual Studio Code

Open the project folder in Visual Studio Code (VS Code) and select the Startup.cs file.. VS Code will prompt to restore the needed project dependencies and add build/debug dependencies. Tap Yes to add the build and debug assets and then tap Restore to restore the project dependencies.

Info messages: 2. 2. Required assets to build and debug are missing from your project. Add them?

For Restore, alternately, you can run dotnet restore from the terminal or enter ⌘⇧P or Ctrl+Shift+P in VS Code and then type .NET as shown:

Command bar showing autocompletion option on typing 'dot' for 'dotnet: Restore Packages'

VS Code provides a streamlined, clean interface for working with files and a productive coding enviromment.

In the left navigation bar, there are five icons, representing four viewlets:

  • Explore
  • Search
  • Git
  • Debug
  • Extensions

The Explorer viewlet provides folder navigation and a view of the files you have open. It displays a badge to indicate files with unsaved changes. You can create new folders and files in the viewlet. You can select Save All from a menu option that appears on mouse over.

The Search viewlet allows you to search the folder tree of files you have open. The search is for filenames and file contents.

VS Code will integrate with Git if it is installed on your system. You can initialize a new repository, make commits, and push changes from the Git viewlet.

GIT sidebar indicating 'This workspace isn't yet under git source control' with an 'Initialize git repository' button

The Debug viewlet supports interactive debugging of applications.

VS Code's editor has a ton of great features. You'll notice unused using statements are underlined and can be removed automatically by using ⌘ . or Ctrl + . when the lightbulb icon appears. Classes and methods also display how many references there are in the project to them.

More on editor in Visual Studio Code.

Using the VS Code debugger

The sample is configured to use Kestrel for the web server.

Run the app in the debugger:

  • Tap the Debug icon in the View Bar on the left pane

  • Tap the "Play (F5)" icon to launch the app

DEBUG sidebar showing the triangle play button

Your default browser will automatically launch and navigate to http://localhost:5000

Browser window

  • To stop the application, close the browser and hit the "Stop" icon on the debug bar

VS Code Debug bar

Using the dotnet commands

  • Run dotnet run command to launch the app from terminal/bash

  • Navigate to http://localhost:5000

  • To stop the web server enter ⌃+C or Ctrl+C.

Publishing to Azure

VS Code provides Git integration to push updates to production, hosted on Microsoft Azure.

Initialize Git

Initialize Git in the folder you're working in. Tap on the Git viewlet and click the Initialize Git repository button.

GIT sidebar

Add a commit message and tap enter or tap the checkmark icon to commit the staged files.

GIT sidebar showing file changes

Git is tracking changes, so if you make an update to a file, the Git viewlet will display the files that have changed since your last commit.

Initialize Azure Website

You can deploy to Azure Web Apps directly using Git.

Create a Web App in the Azure Portal to host your new application.

Microsoft Azure Portal: New button: Web + Mobile selection in the Marketplace list reveals a Web App button under Featured Apps

Configure the Web App in Azure to support continuous deployment using Git.

Record the Git URL for the Web App from the Azure portal.

Azure Portal for web application: Overview panel

In a Terminal window, add a remote named azure with the Git URL you noted previously.

git remote add azure https://shayneboyer@myfirstappmac.scm.azurewebsites.net:443/MyFirstAppMac.git

Push to master. git push azure master to deploy.

Command window showing a successful deployment

Browse to the newly deployed web app.

Browser window

Looking at the Deployment Details in the Azure Portal, you can see the logs and steps each time there is a commit to the branch.

Azure Portal for web application: Deployment Details

Additional resources