Get the most from each lesson's compiled editor—the same habits transfer to Visual Studio, Rider, VS Code with C# Dev Kit, and CI running dotnet build.
Recommended workflow
- Read the concept section before editing code.
- Click Run to compile with
dotnetand execute. - Use
Console.WriteLinefor debug output. - Fix build errors and nullable warnings promptly—they prevent runtime surprises.
What the runner can and cannot do
- Can — single-file console snippets with top-level statements and
Console.WriteLine - Needs local setup — multi-project solutions, NuGet-heavy apps, Unity Editor play mode
Compare workflows with Java, JavaScript, and C++ compiled tracks.
Self-check
- What API prints lines in C# lessons?
- What CLI command runs a console project locally?
Challenge
First dotnet run
- Click Run with the default code.
- Confirm output appears in the terminal.
- Add a second
Console.WriteLinewith your name.
Done when: the terminal shows the default message and your custom line.
Challenge
Verify dotnet output
- Run the default program.
- Confirm output in the terminal.
- Add a deliberate type error and read the compiler message.
- Fix and run again.
Done when: you see Roslyn compiler errors when appropriate and clean output after fixing.
Interview prep
- What does the playground compile with?
A temporary .NET 8 console project via
dotnet run—Roslyn compiles your C# and the CLR executes the output.