Compile error in Visual Studio 2019

[ffMathy]

I get the following error:

ETSDK1013 The TargetFramework value '' was not recognized. It may be misspelled. If not, then the TargetFrameworkIdentifier and/or TargetFrameworkVersion properties must be specified explicitly. System.Text.Json (src\System.Text.Json) C:\Program Files\dotnet\sdk\3.0.100\Sdks\Microsoft.NET.Sdk\targets\Microsoft.NET.TargetFrameworkInference.targets

When trying to compile System.Text.Json.

I really want to contribute more, so this is a bummer.

[ahsonkhan]

Did you first build the repo via the command line?

If on windows, run build.cmd at the root of the repo first, then you should be able to build/test S.T.Json via the command line/in VS.

https://github.com/dotnet/corefx/blob/master/Documentation/project-docs/developer-guide.md#building-the-repository

[ericstj]

+1 to what @ahsonkhan said. Also, be sure to have the latest .NETCore 3.0 SDK installed as we now depend on it (when opening in VS). If you don't wish to install it you can launch the sln from the root, after building once, using build -vs System.Text.Json. The latter will allow you to run tests in test explorer as well. Let us know if you have any issues.

[ViktorHofer]

Closing as resolved. Feel free to reopen if you still encounter the issue.