<ul><li>The tutorial explains how to run C# code without a project file using the .NET 10 Preview SDK.</li><li>This approach is helpful for quick tests, learning, and simple scripts without a full project structure.</li><li>Using dotnet run file.cs, you can directly compile and run C# programs without a .csproj setup.</li><li>You start by creating a C# source file named app.cs with basic code like printing to the console.</li><li>The CLI implicitly creates a project definition based on the default dotnet new console template to compile and run the file.</li><li>You can reference NuGet packages directly within the source file using app directives like #:package.</li><li>Advanced options include specifying SDK, properties, and using directives for finer control.</li><li>On Unix-like systems, you can make C# files executable like shell scripts using a shebang line.</li><li>The file-based execution model in .NET 10 Preview is recommended for simplicity and quick tasks, not for complex applications.</li><li>To transition to a full project structure, you can use dotnet project convert app.cs.</li></ul>

Tutorial: Running Your C# Code Without a Project File

Discover more