The information in this article applies to .NET 5 and later. For UWP projects, see the article onChoosing a UWP version.

The C# language reference documents the most recently released version of the C# language. It also contains initial documentation for features in public previews for the upcoming language release.

The documentation identifies any feature first introduced in the last three versions of the language or in current public previews.

In Visual Studio, the option to change the language version through the UI is disabled because the default version aligns with the project's target framework (TFM). This default configuration ensures compatibility between language features and runtime support. To change the language version in Visual Studio, change the project's target framework.

For example, changing the targetTFM (for example, from.NET 6 to.NET 9) updates the language version accordingly, from C# 10 to C# 13. This approach prevents issues with runtime compatibility and minimizes unexpected build errors due to unsupported language features.

If you need a specific language version that differs from the one automatically selected, use the methods in this article to override the default settings directly in the project file.

If you must specify your C# version explicitly, you can do so in several ways:

• Manually edit theproject file.
• Set the language versionfor multiple projects in a subdirectory.
• Configure theLangVersion compiler option.

Edit the project file

Set the language version in your project file. The project file is the*.csproj file in the root folder for your project. For example, if you want explicit access to preview features, add an element like the following example:

<PropertyGroup>   <LangVersion>preview</LangVersion></PropertyGroup>

The valuepreview uses the latest available preview C# language version your compiler supports.

Configure multiple projects

To configure multiple C# projects, create aDirectory.Build.props file, typically in your solution directory, that contains the<LangVersion> element. Add the following setting to theDirectory.Build.props file:

<Project> <PropertyGroup>   <LangVersion>preview</LangVersion> </PropertyGroup></Project>

Builds in all subdirectories of the directory containing that file now use the preview C# version. For more information, seeCustomize your build.

C# language version reference

The following table shows all current C# language versions. Older compilers might not understand every value. If you install the latest .NET SDK, you have access to everything listed.