-langversion (C# Compiler Options)

• 08/23/2019
• 3 minutes to read
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Causes the compiler to accept only syntax that is included in the chosen C# language specification.

Syntax

-langversion:option

Arguments

option
The following values are valid:

The default language version depends on the target framework for your application and the version of the SDK or Visual Studio installed. Those rules are defined in the configuring the language version article.

Remarks

Metadata referenced by your C# application is not subject to -langversion compiler option.

Because each version of the C# compiler contains extensions to the language specification, -langversion does not give you the equivalent functionality of an earlier version of the compiler.

Additionally, while C# version updates generally coincide with major .NET Framework releases, the new syntax and features are not necessarily tied to that specific framework version. While the new features definitely require a new compiler update that is also released alongside the C# revision, each specific feature has its own minimum .NET API or common language runtime requirements that may allow it to run on downlevel frameworks by including NuGet packages or other libraries.

Regardless of which -langversion setting you use, you will use the current version of the common language runtime to create your .exe or .dll. One exception is friend assemblies and -moduleassemblyname (C# Compiler Option), which work under -langversion:ISO-1.

For other ways to specify the C# language version, see the Select the C# language version article.

For information about how to set this compiler option programmatically, see LanguageVersion.

C# language specification

Minimum SDK version needed to support all language features

The following table lists the minimum versions of the SDK with the C# compiler that supports the corresponding language version:

See also

• C# Compiler Options
• Managing Project and Solution Properties