Phil's Notes

Using C# 9.0 with Any Project on Visual Studio 2019

c#

Even though Visual Studio 2019 comes with C# 9.0, not all new projects will start with C# 9.0. For example, if you start a .NET Core 3.1 project, it will default to C# 8.0. However, it is possible to change it to use C# 9.0 having to install anything else.

Framework Version C# Default Version
.NET 5.x 9.0
.NET Core 3.x 8.0
.NET Core 2.x 7.3
.NET Framework any 7.3

Reference: MS Docs

If you start a .NET 5.0 project, you don't need to change anything, otherwise, if you want to change the version, follow these steps:

  1. Right-click on your Project in the Solution Explorer, click Unload Project.
  2. In the .csproj file that shows up, add this line to the <PropertyGroup>:
<LangVersion>9</LangVersion>
  1. Right-click on your Project in the Solution and click Reload Project