This article will show you how to write your first ASP.NET Core application on macOS or Linux.
Setting up your development environment
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.
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.
- 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.
For Restore, alternately, you can run
dotnet restore from the terminal or enter
Ctrl+Shift+P in VS Code and then type
.NET as shown:
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:
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.
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
Your default browser will automatically launch and navigate to
- To stop the application, close the browser and hit the "Stop" icon on the debug bar
Using the dotnet commands
dotnet runcommand to launch the app from terminal/bash
To stop the web server enter
Publishing to Azure
VS Code provides Git integration to push updates to production, hosted on Microsoft Azure.
Initialize Git in the folder you're working in. Tap on the Git viewlet and click the
Initialize Git repository button.
Add a commit message and tap enter or tap the checkmark icon to commit the staged files.
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.
- If you don't have an Azure account, you can create a free trial.
Create a Web App in the Azure Portal to host your new application.
Configure the Web App in Azure to support continuous deployment using Git.
Record the Git URL for the Web App from the Azure portal.
In a Terminal window, add a remote named
azure with the Git URL you noted previously.
git remote add azure https://firstname.lastname@example.org:443/MyFirstAppMac.git
Push to master.
git push azure master to deploy.
Browse to the newly deployed web app.
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.