.Net 5.0 using older SDK, Core, Standard packages

[xbotuk]

I would like to know if .Net 5.0 can use libraries from older SDK, Core, Standard packages easily. If so how and which older versions will be supported?

[jnm2]

A project targeting .NET 5 can use libraries which target:

• .NET 5
• Any version of .NET Core (1.0–3.1)
• Any version of .NET Standard (1.0–2.1)
• Any version of .NET Framework (1.0–4.8) BUT with a build warning and no guarantee against MissingMethodException if the library tries to access something that is in .NET Framework that is not in .NET 5. https://docs.microsoft.com/en-us/dotnet/standard/analyzers/portability-analyzer can tell you whether the library might do this.

If so how

The same way you would reference a .NET 5 library. Using <PackageReference Include="SomePackageId" Version="1.2.3" /> is the standard way, but you can also use <Reference Include="Path/to/SomeAssemblyFile.dll" />.