Build reliable habits in the C# playground—the same debugging loop transfers to local ASP.NET Core with dotnet watch run and your IDE.
Recommended workflow
- Read the concept section before editing code.
- Click Run to compile and execute C# on the dev runner.
- Use
Console.WriteLinefor output; use classes and LINQ to simulate web patterns. - Change one idea at a time—one route map entry, one middleware step, one LINQ filter.
- When lessons show
dotnet new web, run commands locally after installing the .NET SDK. - Reset the editor if you drift far from the lesson goal.
What the runner can and cannot do
- Can — C# top-level statements, LINQ, async/await basics, simulated routing/DI/EF logic
- Conceptual — Razor views, Kestrel hosting, middleware pipeline, EF migrations
- Needs local setup — real web project, SQL Server/PostgreSQL, HTTPS certs, IIS/nginx reverse proxy
Review JavaScript async if await feels unfamiliar—ASP.NET controllers use async heavily for I/O.
Self-check
- Why does this track simulate web patterns in plain C#?
- When should you install the .NET SDK on your machine?
Challenge
First compile and run
- Click Run with the default code.
- Confirm the runtime version prints in the output.
- Add a second
Console.WriteLinewith a custom message.
Done when: the terminal shows the runtime version and your custom message.