您在Visual Studio解释csproj文件的方式中遇到了一个已知问题.在命令行(msbuild.exe或dotnet.exe)上，可以使用导入的文件中的属性TargetFramework来构建项目.但是，Visual Studio在导入时无法识别它.

You've hit a known issue in the way that Visual Studio interprets csproj files. On command line (msbuild.exe or dotnet.exe) you can build a project with the property TargetFramework coming in from an imported file. Visual Studio, however, does not recognize this when it is imported.

请参见 https://github.com/dotnet/project-system/issues/1358 .