Lesson 8 / 26

Target Framework and Language Version

Choose a target framework and understand how the C# language version follows it.

TargetFramework

TargetFramework such as net10.0 says which .NET APIs your project may use. Prefer a Long-Term Support (LTS) release for production because it gets patches for longer.

Pieces that fit together

A solution groups projects, projects reference each other, and NuGet supplies outside libraries.

Solution, project and NuGet package connected in order. — Figure 3.1 — Solution, projects and packages.

Multi-targeting a library

A shared library can build for several frameworks at once. Note the plural TargetFrameworks.

<PropertyGroup>
  <TargetFrameworks>net8.0;net10.0</TargetFrameworks>
</PropertyGroup>

Language version follows the framework

Each target framework has a default C# version, so you rarely set LangVersion yourself. Forcing a newer one on an old framework can break features that need runtime support.

Quick check: Why choose an LTS release for production?

It receives fixes for a longer time
It is always faster
It needs no SDK
It is the only one that runs on Linux

Answer

It receives fixes for a longer time — LTS releases are supported longer, which reduces forced upgrades.