Question: GetConnectionString in Microsoft.Extensions.Configuration.ConfigurationExtensions

Asp.NET Core v3.0

In VS2019 I press F12 while method GetConnectionString is in focus and a metadata file opens, where it shows the location of the source code:

// C:\Program Files\dotnet\packs\Microsoft.AspNetCore.App.Ref\3.0.0\ref\netcoreapp3.0\Microsoft.Extensions.Configuration.Abstractions.dll

Now when I open the above dll, my Decompiler shows

public static string GetConnectionString(this IConfiguration configuration, string name) { throw null; }

But this is not the implementation. So I searched for it in this repo and found this ref branch which depicts this code above and a src branch which shows the actual implementation:

public static string GetConnectionString(this IConfiguration configuration, string name) { return configuration?.GetSection("ConnectionStrings")?[name]; }

What is the `ref` branch? Or better, why do I not see the real implementation when using my decompiler

Ref branch: src/Configuration/Config.Abstractions/ref/Microsoft.Extensions.Configuration.Abstractions.netstandard2.0.cs

Src branch: src/Configuration/Config.Abstractions/src/ConfigurationExtensions.cs

[MSDN-WhiteKnight]

It does not make decompiler obsolete, you just have to supply actual implementation assembly as input for it. It is contained in Microsoft.Extensions.Configuration.Abstractions in lib subdirectory. It should be cached somewhere on your local disk if you were recently building something targeting it; or you can load it from NuGet Gallery yourself if it’s not.

No idea why source.dot.net currently works so horribly and fails to find half of BCL types, though. Hope that’s just a temporary issue.

[gfoidl]

In short: it is better for tooling (Visual Studio).

Further infos:

• Reference assemblies
• What are reference assemblies?
• evolution-of-design-time-assemblies